title: Date of Easter

text: The epacts are used to find the dates of the new moon in the following way: Write down a table of all 365 days of the year (the leap day is ignored). Then label all dates with a Roman numeral counting downwards, from "*" (0 or 30), "xxix" (29), down to "i" (1), starting from 1 January, and repeat this to the end of the year. However, in every second such period count only 29 days and label the date with xxv (25) also with xxiv (24). Treat the 13th period (last eleven days) as long, therefore, and assign the labels "xxv" and "xxiv" to sequential dates (26 and 27 December respectively). Finally, in addition, add the label "25" to the dates that have "xxv" in the 30-day periods; but in 29-day periods (which have "xxiv" together with "xxv") add the label "25" to the date with "xxvi". The distribution of the lengths of the months and the length of the epact cycles is such that each civil calendar month starts and ends with the same epact label, except for February and, one might say, for August, which starts with the double label "xxv"/"xxiv" but ends with the single label "xxiv". This table is called the . The ecclesiastical new moons for any year are those dates when the epact for the year is entered. If the epact for the year is for instance 27, then there is an ecclesiastical new moon on every date in that year that has the epact label "xxvii" (27). If the epact is 25, then there is a complication, introduced so that the ecclesiastical new moon will not fall on the same date twice during a Metonic cycle. If the epact cycle in force includes epact 24 (as does the cycle in use since 1900 and until 2199), then an epact of 25 puts the ecclesiastical new moon on April 4 (having the label "25"), otherwise it is on April 5 (having label "xxv"). In fact, an epact of 25 giving April 4 can only happen if the golden number is greater than 11 (in which case it will be 11 years after a year with epact 24). So for example, in 1954 the golden number was 17, the epact was 25, the ecclesiastical new moon was reckoned on April 4, the full moon on April 17, and Easter was on April 18 rather than April 25 as it would otherwise have been, such as in 1886 when the golden number was 6.


title: Date of Easter

text: Also label all the dates in the table with letters "A" to "G", starting from 1 January, and repeat to the end of the year. If, for instance, the first Sunday of the year is on 5 January, which has letter "E", then every date with the letter "E" is a Sunday that year. Then "E" is called the dominical letter for that year (from , the Lord's day). The dominical letter cycles backward one position every year. However, in leap years after 24 February the Sundays fall on the previous letter of the cycle, so leap years have two dominical letters: the first for before, the second for after the leap day.


title: Date of Easter

text: In practice, for the purpose of calculating Easter, this need not be done for all 365 days of the year. For the epacts, March comes out exactly the same as January, so one need not calculate January or February. To also avoid the need to calculate the Dominical Letters for January and February, start with D for 1 March. You need the epacts only from 8 March to 5 April. This gives rise to the following table:


title: Date of Easter

text: Example: If the epact is 27 (xxvii), an ecclesiastical new moon falls on every date labeled "xxvii". The ecclesiastical full moon falls 13 days later. From the table above, this gives a new moon on 4 March and 3 April, and so a full moon on 17 March and 16 April.


title: Date of Easter

text: Then Easter Day is the first Sunday after the first ecclesiastical full moon on or after 21 March. This definition uses "on or after 21 March" to avoid ambiguity with historic meaning of the word "after". In modern language, this phrase simply means "after 20 March". The definition of "on or after 21 March" is frequently incorrectly abbreviated to "after 21 March" in published and web-based articles, resulting in incorrect Easter dates.


title: Date of Easter

text: In the example, this paschal full moon is on 16 April. If the dominical letter is E, then Easter day is on 20 April.


title: Date of Easter

text: The label "25" (as distinct from "xxv") is used as follows: Within a Metonic cycle, years that are 11 years apart have epacts that differ by one day. A month beginning on a date having labels xxiv and xxv written side by side has either 29 or 30 days. If the epacts 24 and 25 both occur within one Metonic cycle, then the new (and full) moons would fall on the same dates for these two years. This is possible for the real moon but is inelegant in a schematic lunar calendar; the dates should repeat only after 19 years. To avoid this, in years that have epacts 25 and with a Golden Number larger than 11, the reckoned new moon falls on the date with the label "25" rather than "xxv". Where the labels "25" and "xxv" are together, there is no problem since they are the same. This does not move the problem to the pair "25" and "xxvi", because the earliest epact 26 could appear would be in year 23 of the cycle, which lasts only 19 years: there is a in between that makes the new moons fall on separate dates.


title: Date of Easter

text: The Gregorian calendar has a correction to the tropical year by dropping three leap days in 400 years (always in a century year). This is a correction to the length of the tropical year, but should have no effect on the Metonic relation between years and lunations. Therefore, the epact is compensated for this (partially see epact) by subtracting one in these century years. This is the so-called solar correction or "solar equation" ("equation" being used in its medieval sense of "correction").


title: Date of Easter

text: However, 19 uncorrected Julian years are a little longer than 235 lunations. The difference accumulates to one day in about 310 years. Therefore, in the Gregorian calendar, the epact gets corrected by adding 1 eight times in 2,500 (Gregorian) years, always in a century year: this is the so-called lunar correction (historically called "lunar equation"). The first one was applied in 1800, the next is in 2100, and will be applied every 300 years except for an interval of 400 years between 3900 and 4300, which starts a new cycle. At the time of the reform, the epacts were changed by 7, even though 10 days were skipped, in order to make a three-day correction to the timing of the new moons.


title: Date of Easter

text: The solar and lunar corrections work in opposite directions, and in some century years (for example, 1800 and 2100) they cancel each other. The result is that the Gregorian lunar calendar uses an epact table that is valid for a period of from 100 to 300 years. The epact table listed above is valid for the period 1900 to 2199.


title: Date of Easter

text: As explained below, the dates of Easter repeat after 5,700,000 years, and over this period the average length of an ecclesiastical month is 2,081,882,250/70,499,183 ≈ 29.5305869 days, which differs from the current actual mean lunation length (29,5305889 d: see Lunar month#Synodic month) in the 6th figure after the decimal point. This corresponds to an error of less than a day in the phase of the moon over 40,000 years, but in fact the length of a day is changing (as is the length of a synodic month), so the system is not accurate over such periods. See the article ΔT (timekeeping) for information on the cumulative change of day length.


title: Date of Easter

text: Every other lunar month has only 29 days, so one day must have two (of the 30) epact labels assigned to it. The reason for moving around the epact label "xxv/25" rather than any other seems to be the following: According to Dionysius (in his introductory letter to Petronius), the Nicene council, on the authority of Eusebius, established that the first month of the ecclesiastical lunar year (the paschal month) should start between 8 March and 5 April inclusive, and the 14th day fall between 21 March and 18 April inclusive, thus spanning a period of (only) 29 days. A new moon on 7 March, which has epact label "xxiv", has its 14th day (full moon) on 20 March, which is too early (not following 20 March). So years with an epact of "xxiv", if the lunar month beginning on 7 March had 30 days, would have their paschal new moon on 6 April, which is too late: The full moon would fall on 19 April, and Easter could be as late as 26 April. In the Julian calendar the latest date of Easter was 25 April, and the Gregorian reform maintained that limit. So the paschal full moon must fall no later than 18 April and the new moon on 5 April, which has epact label "xxv". 5 April must therefore have its double epact labels "xxiv" and "xxv". Then epact "xxv" must be treated differently, as explained in the paragraph above.


title: Date of Easter

text: The frequency distribution for the date of Easter is ill-defined, because every 100 to 300 years the mapping from golden number to epact changes, and the long-term frequency distribution is only valid over a period of millions of years (see below), whereas the system will certainly not be used for that long.


title: Date of Easter

text: The present mapping, valid from 1900 to 2199, gives Easter dates with highly varying frequencies. March 22 can never occur, whereas March 31 occurs 13 times in this 300-year span.


title: Date of Easter

text: If one does ask the question of what the distribution would be in the long term, that is, over the whole 5.7-million-year period after which the dates repeat, this distribution can be found fairly simply, and is quite different from the distribution in the period 1900 to 2199, or even the distribution over the period since the reform until now. The date of Easter in a given year depends only on the epact for the year, its golden number, and its dominical letter, which tells us which days are Sundays (more precisely, the dominical letter for the part of the year after February, which is different in leap years form the letter for January and February). (The golden number only matters when the epact is 25, as explained earlier.) If we go forward 3,230,000 years from a particular year, we find a year at the same point in the 400-year Gregorian cycle and with the same golden number, but with the epact augmented by 1. Therefore, in the long term, all thirty epacts are equally likely. On the other hand, the dominical leters do not all have the same frequency – years with the letters A and C (at the end of the year) occur 14% of the time each, E and F occur 14.25% of the time, and B, D, and G occur 14.5% of the time. Taking into consideration the complication having to do with epact 25, this gives the distribution shown in the second graph. April 19 is the most common because when the epact is 25 the ecclesiastical full moon falls on April 17 or 18 (depending on the golden number), and it also falls on these dates when the epact is 26 or 24, respectively. There are seven days on which the full moon can fall, including April 17 and April 18, in order for Easter to be on April 19. As a consequence, 19 April is the date on which Easter falls most frequently in the Gregorian calendar, with a frequency of 29/750 (about 3.867% of the years). April 18 is the second most common, because of the extra times that the full moon is on the 17th. 22 March is the least frequent, with a frequency of 29/6000 (0.467%).


title: Date of Easter

text: As a consequence, 19 April is the date on which Easter falls most frequently in the Gregorian calendar, in about 3.87% of the years. 22 March is the least frequent, with 0.48%.


title: Date of Easter

text: The relation between lunar and solar calendar dates is made independent of the leap day scheme for the solar year. Basically the Gregorian calendar still uses the Julian calendar with a leap day every four years, so a Metonic cycle of 19 years has 6,940 or 6,939 days with five or four leap days. Now the lunar cycle counts only . By not labeling and counting the leap day with an epact number, but having the next new moon fall on the same calendar date as without the leap day, the current lunation gets extended by a day, and the 235 lunations cover as many days as the 19 years (so long as the 19 years do not include a "solar correction" as in 1900). So the burden of synchronizing the calendar with the moon (intermediate-term accuracy) is shifted to the solar calendar, which may use any suitable intercalation scheme, all under the assumption that 19 solar years = 235 lunations (creating a long-term inaccuracy if not corrected by a "lunar correction"). A consequence is that the reckoned age of the moon may be off by a day, and also that the lunations that contain the leap day may be 31 days long, which would never happen if the real moon were followed (short-term inaccuracies). This is the price of a regular fit to the solar calendar.


title: Date of Easter

text: From the perspective of those who might wish to use the Gregorian Easter cycle as a calendar for the entire year, there are some flaws in the Gregorian lunar calendar (although they have no effect on the paschal month and the date of Easter):


title: Date of Easter

text: A careful analysis shows that through the way they are used and corrected in the Gregorian calendar, the epacts are actually fractions of a lunation (, also known as a "tithi") and not full days. See epact for a discussion.


title: Date of Easter

text: The solar and lunar corrections repeat after centuries. In that period, the epact for a given golden number changes by a total of . This is prime to the 30 possible epacts, so it takes before the epact mappings repeat; and centuries before they repeat at the same golden number. It is not obvious how many ecclesiastic New Moons are counted in this 5.7 Myr period. The Metonic cycles add up to = 70,500,000 lunations. But there are net corrections to the epacts, which divided by 30 add up to a correction of −817 lunations, for a total of 70,499,183 lunations. This number appears to have been first derived by Magnus Georg Paucker in 1837. It is also mentioned in the chapter on calendars (p. 744) in the Nautical Almanac of 1931 and in the Explanatory Supplement of 1992 (p. 582). So the Gregorian Easter dates repeat in exactly the same order only after 5,700,000 years, 70,499,183 lunations, or 2,081,882,250 days; the mean lunation length is then 2,081,882,250/70,499,183 = 29.53058690 days. Of course the calendar would have to be adjusted after a few millennia because of changes in the length of the tropical year, the synodic month, and the day.


title: Date of Easter

text: This raises the question why the Gregorian lunar calendar has separate solar and lunar corrections, which sometimes cancel each other. Lilius's original work has not been preserved, but his proposal was described in the circulated in 1577, in which it is explained that the correction system he devised was to be a perfectly flexible tool in the hands of future calendar reformers, since the solar and lunar calendar could henceforth be corrected without mutual interference. An example of this flexibility was provided through an alternative intercalation sequence derived from Copernicus's theories, along with its corresponding epact corrections.


title: Date of Easter

text: The "solar corrections" approximately undo the effect of the Gregorian modifications to the leap days of the solar calendar on the lunar calendar: they (partially) bring the epact cycle back to the original Metonic relation between the Julian year and lunar month. The inherent mismatch between sun and moon in this basic 19-year cycle is then corrected every three or four centuries by the "lunar correction" to the epacts. However, the epact corrections occur at the beginning of Gregorian centuries, not Julian centuries, and therefore the original Julian Metonic cycle is not fully restored.


title: Date of Easter

text: While the net subtractions could be distributed evenly over 10,000 years (as has been proposed for example by ) if the corrections are combined, then the inaccuracies of the two cycles are also added and cannot be corrected separately.


title: Date of Easter

text: The ratios of (mean solar) days per year and days per lunation change both because of intrinsic long-term variations in the orbits, and because the rotation of the Earth is slowing down due to tidal deceleration, so the Gregorian parameters become increasingly obsolete.


title: Date of Easter

text: This does affect the date of the equinox, but it so happens that the interval between northward (northern hemisphere spring) equinoxes has been fairly stable over historical times, especially if measured in mean solar time.


title: Date of Easter

text: Also the drift in ecclesiastical full moons calculated by the Gregorian method compared to the true full moons is affected less than one would expect, because the increase in the length of the day is almost exactly compensated for by the increase in the length of the month, as tidal braking transfers angular momentum of the rotation of the Earth to orbital angular momentum of the Moon.


title: Date of Easter

text: The Ptolemaic value of the length of the mean synodic month, established around the 4th century BCE by the Babylonians, is (see Kidinnu); the current value is 0.46 s less (see New moon). In the same historic stretch of time the length of the mean tropical year has diminished by about 10 s (all values mean solar time).


title: Date of Easter

text: The portion of the Tabular methods section above describes the historical arguments and methods by which the present dates of Easter Sunday were decided in the late 16th century by the Catholic Church. In Britain, where the Julian calendar was then still in use, Easter Sunday was defined, from 1662 to 1752 (in accordance with previous practice), by a simple table of dates in the Anglican Prayer Book (decreed by the Act of Uniformity 1662). The table was indexed directly by the golden number and the Sunday letter, which (in the Easter section of the book) were presumed to be already known.


title: Date of Easter

text: For the British Empire and colonies, the new determination of the Date of Easter Sunday was defined by what is now called the Calendar (New Style) Act 1750 with its Annexe. The method was chosen to give dates agreeing with the Gregorian rule already in use elsewhere. The Act required that it be put in the Book of Common Prayer, and therefore it is the general Anglican rule. The original Act can be seen in the British "Statutes at Large 1765". The Annexe to the Act includes the definition: ""Easter-day" (on which the rest depend) is always the first "Sunday" after the "Full Moon", which happens upon, or next after the Twenty-first Day of "March". And if the "Full Moon" happens upon a "Sunday", "Easter-day" is the "Sunday" after." The Annexe subsequently uses the terms "Paschal Full Moon" and "Ecclesiastical Full Moon", making it clear that they approximate to the real full moon.


title: Date of Easter

text: The method is quite distinct from that described above in Gregorian reform of the. For a general year, one first determines the golden number, then one uses three tables to determine the Sunday letter, a "cypher", and the date of the paschal full moon, from which the date of Easter Sunday follows. The epact does not explicitly appear. Simpler tables can be used for limited periods (such as 1900–2199) during which the cypher (which represents the effect of the solar and lunar corrections) does not change. Clavius's details were employed in the construction of the method, but they play no subsequent part in its use.


title: Date of Easter

text: J. R. Stockton shows his derivation of an efficient computer algorithm traceable to the tables in the Prayer Book and the Calendar Act (assuming that a description of how to use the Tables is at hand), and verifies its processes by computing matching Tables.


title: Date of Easter

text: The method for computing the date of the ecclesiastical full moon that was standard for the western Church before the Gregorian calendar reform, and is still used today by most eastern Christians, made use of an uncorrected repetition of the 19-year Metonic cycle in combination with the Julian calendar. In terms of the method of the epacts discussed above, it effectively used a single epact table starting with an epact of 0, which was never corrected. In this case, the epact was counted on 22 March, the earliest acceptable date for Easter. This repeats every 19 years, so there are only 19 possible dates for the paschal full moon from 21 March to 18 April inclusive.


title: Date of Easter

text: Because there are no corrections as there are for the Gregorian calendar, the ecclesiastical full moon drifts away from the true full moon by more than three days every millennium. It is already a few days later. As a result, the eastern churches celebrate Easter one week later than the western churches about 50% of the time. (The eastern Easter is occasionally four or five weeks later because the Julian calendar is 13 days behind the Gregorian in 1900–2099, and so the Gregorian paschal full moon is sometimes before Julian 21 March.)


title: Date of Easter

text: The sequence number of a year in the 19-year cycle is called its golden number. This term was first used in the computistic poem by Alexander de Villa Dei in 1200. A later scribe added the golden number to tables originally composed by Abbo of Fleury in 988.


title: Date of Easter

text: The claim by the Catholic Church in the 1582 papal bull , which promulgated the Gregorian calendar, that it restored "the celebration of Easter according to the rules fixed by ... the great ecumenical council of Nicaea" was based on a false claim by Dionysius Exiguus (525) that "we determine the date of Easter Day ... in accordance with the proposal agreed upon by the 318 Fathers of the Church at the Council in Nicaea." The First Council of Nicaea (325) did not, however, provide any explicit rules to determine that date, but only wrote "all our brethren in the East who formerly followed the custom of the Jews are henceforth to celebrate the said most sacred feast of Easter at the same time with the Romans and yourselves [the Church of Alexandria] and all those who have observed Easter from the beginning." The medieval was based on the Alexandrian , which was developed by the Church of Alexandria during the first decade of the 4th century using the Alexandrian calendar. The eastern Roman Empire accepted it shortly after 380 after converting the to the Julian calendar. Rome accepted it sometime between the sixth and ninth centuries. The British Isles accepted it during the eighth century except for a few monasteries. Francia (all of western Europe except Scandinavia (pagan), the British Isles, the Iberian peninsula, and southern Italy) accepted it during the last quarter of the eighth century. The last Celtic monastery to accept it, Iona, did so in 716, whereas the last English monastery to accept it did so in 931. Before these dates, other methods produced Easter Sunday dates that could differ by up to five weeks.


title: Date of Easter

text: As mentioned earlier, these Paschal full moons are 4, 5 or 34 days later than in the Western system, and are around three days later than the astronomical full moon. For example, the April 2015 lunar eclipse was on April 4 in the Gregorian calendar, or March 22 in the Julian calendar, but the Paschal full moon for that year (golden number 2) was March 25 in the Julian calendar.


title: Date of Easter

text: The golden number for 1573 is 16 (; ). From the table, the paschal full moon for golden number 16 is 21 March. From the week table 21 March is Saturday. Easter Sunday is the following Sunday, 22 March.


title: Date of Easter

text: So for a given date of the ecclesiastical full moon, there are seven possible Easter dates. The cycle of Sunday letters, however, does not repeat in seven years: because of the interruptions of the leap day every four years, the full cycle in which weekdays recur in the calendar in the same way, is years, the so-called solar cycle. So the Easter dates repeated in the same order after years. This paschal cycle is also called the Victorian cycle, after Victorius of Aquitaine, who introduced it in Rome in 457. It is first known to have been used by Annianus of Alexandria at the beginning of the 5th century. It has also sometimes erroneously been called the Dionysian cycle, after Dionysius Exiguus, who prepared Easter tables that started in 532; but he apparently did not realize that the Alexandrian he described had a 532-year cycle, although he did realize that his 95-year table was not a true cycle. Venerable Bede (7th century) seems to have been the first to identify the solar cycle and explain the paschal cycle from the Metonic cycle and the solar cycle.


title: Date of Easter

text: In medieval western Europe, the dates of the paschal full moon (14 Nisan) given above could be memorized with the help of a 19-line alliterative poem in Latin:


title: Date of Easter

text: The first half-line of each line gives the date of the paschal full moon from the table above for each year in the 19-year cycle. The second half-line gives the , or weekday displacement, of the day of that year's paschal full moon from the , or the weekday of 24 March. The is repeated in Roman numerals in the third column.


title: Date of Easter

text: Due to the discrepancies between the approximations of Computistical calculations of the time of the mean (northern hemisphere) vernal equinox and the lunar phases, and the true values computed according to astronomical principles, differences occasionally arise between the date of Easter according to computistical reckoning and the hypothetical date of Easter calculated by astronomical methods using the principles attributed to the Church fathers. These discrepancies are called "paradoxical" Easter dates. In his of 1474, Regiomontanus computed the exact time of all conjunctions of the Sun and Moon for the longitude of Nuremberg according to the Alfonsine Tables for the period from 1475 to 1531. In his work he tabulated 30 instances where the Easter of the Julian disagreed with Easter computed using astronomical New Moon. In eighteen cases the date differed by a week, in seven cases by 35 days, and in five cases by 28 days.


title: Date of Easter

text: Ludwig Lange investigated and classified different types of paradoxical Easter dates using the Gregorian . In cases where the first vernal full moon according to astronomical calculation occurs on a Sunday and the gives the same Sunday as Easter, the celebrated Easter occurs one week in advance compared to the hypothetical "astronomically" correct Easter. Lange called this case a negative weekly (hebdomadal) paradox (H− paradox). If the astronomical calculation gives a Saturday for the first vernal full moon and Easter is not celebrated on the directly following Sunday but one week later, Easter is celebrated according to the one week too late in comparison to the astronomical result. He classified such cases a positive weekly (hebdomadal) paradox (H+ paradox). The discrepancies are even larger if there is a difference according to the vernal equinox with respect to astronomical theory and the approximation of the . If the astronomical equinoctial full moon falls before the computistical equinoctial full moon, Easter will be celebrated four or even five weeks too late. Such cases are called a positive equinoctial paradox (A+ paradox) according to Lange. In the reverse case when the Computistical equinoctial full moon falls a month before the astronomical equinoctial full moon, Easter is celebrated four or five weeks too early. Such cases are called a negative equinoctial paradox (A− paradox). Equinoctial paradoxes are always valid globally for the whole earth, because the sequence of equinox and full moon does not depend on the geographical longitude. In contrast, weekly paradoxes are local in most cases and are valid only for part of the earth, because the change of day between Saturday and Sunday is dependent on the geographical longitude. The computistical calculations are based on astronomical tables valid for the longitude of Venice, which Lange called the Gregorian longitude.


title: Date of Easter

text: In the 21st and 22nd centuries negative weekly paradoxical Easter dates occur in 2049, 2076, 2106, 2119 (global), 2133, 2147, 2150, 2170, and 2174; positive weekly paradoxical dates occur in 2045, 2069, 2089 (global), and 2096; positive equinoctial paradoxical dates in 2019, 2038, 2057, 2076, 2095, 2114, 2133, 2152, 2171, and 2190. In 2076 and 2133, double paradoxes (positive equinoctial and negative weekly) occur. Negative equinoctial paradoxes are extremely rare; they occur only twice until the year 4000 in 2353, when Easter is five weeks too early and in 2372, when Easter is four weeks too early.


title: Date of Easter

text: When expressing Easter algorithms without using tables, it has been customary to employ only the integer operations addition, subtraction, multiplication, division, modulo, and assignment as it is compatible with the use of simple mechanical or electronic calculators. That restriction is undesirable for computer programming, where conditional operators and statements, as well as look-up tables, are available. One can easily see how conversion from day-of-March (22 to 56) to day-and-month (22 March to 25 April) can be done as . More importantly, using such conditionals also simplifies the core of the Gregorian calculation.


title: Date of Easter

text: In 1800, the mathematician Carl Friedrich Gauss presented this algorithm for calculating the date of the Julian or Gregorian Easter. He corrected the expression for calculating the variable "p" in 1816. In 1800, he incorrectly stated . In 1807, he replaced the condition with the simpler . In 1811, he limited his algorithm to the 18th and 19th centuries only, and stated that 26 April is always replaced with 19 and 25 April by 18 April in the circumstances stated. In 1816, he thanked his student Peter Paul Tittel for pointing out that "p" was wrong in the original version.


title: Date of Easter

text: An analysis of the Gauss's Easter algorithm is divided into two parts. The first part is the approximate tracking of the lunar orbiting and the second part is the exact deterministic offsetting to obtain a Sunday following the full moon.


title: Date of Easter

text: The first part consists of determining the variable "d", the number of days (counting from 22 March) to the day after the full moon. The formula for "d" contains the terms 19"a" and the constant M. "a" is the year's position in the 19-year lunar phase cycle, in which by assumption the moon's movement relative to earth repeats every 19 calendar years. In older times, 19 calendar years were equated to 235 lunar months (the Metonic cycle), which is remarkably close since 235 lunar months are approximately 6939.6813 days and 19 years are on average 6939.6075 days. The expression (19"a" + M) mod 30 repeats every 19 years within each century as M is determined per century. The 19-year cycle has nothing to do with the '19' in 19"a", it is just a coincidence that another '19' appears. The '19' in 19"a" comes from correcting the mismatch between a calendar year and an integer number of lunar months. A calendar year (non-leap year) has 365 days and the closest one can come with an integer number of lunar months is days. The difference is 11 days, which must be corrected for by moving the following year's occurrence of a full moon 11 days back. But in modulo 30 arithmetic, subtracting 11 is the same as adding 19, hence the addition of 19 for each year added, i.e. 19"a".


title: Date of Easter

text: The M in serves to have a correct starting point at the start of each century. It is determined by a calculation taking the number of leap years up until that century where "k" inhibits a leap day every 100 years and "q" reinstalls it every 400 years, yielding as the total number of inhibitions to the pattern of a leap day every four years. Thus we add to correct for leap days that never occurred. "p" corrects for the lunar orbit not being fully describable in integer terms.


title: Date of Easter

text: The range of days considered for the full moon to determine Easter are 21 March (the day of the ecclesiastical equinox of spring) to 18 April—a 29-day range. However, in the mod 30 arithmetic of variable "d" and constant "M", both of which can have integer values in the range 0 to 29, the range is 30. Therefore, adjustments are made in critical cases. Once "d" is determined, this is the number of days to add to 22 March (the day after the earliest possible full moon allowed, which is coincident with the ecclesiastical equinox of spring) to obtain the date of the day after the full moon.


title: Date of Easter

text: So the first allowable date of Easter is March 22 + d + 0, as Easter is to celebrate the Sunday after the ecclesiastical full moon, that is if the full moon falls on Sunday 21 March Easter is to be celebrated 7 days after, while if the full moon falls on Saturday 21 March Easter is the following 22 March.


title: Date of Easter

text: The second part is finding "e", the additional offset days that must be added to the date offset "d" to make it arrive at a Sunday. Since the week has 7 days, the offset must be in the range 0 to 6 and determined by modulo 7 arithmetic. "e" is determined by calculating . These constants may seem strange at first, but are quite easily explainable if we remember that we operate under mod 7 arithmetic. To begin with, ensures that we take care of the fact that weekdays slide for each year. A normal year has 365 days, but , so 52 full weeks make up one day too little. Hence, each consecutive year, the weekday "slides one day forward", meaning if 6 May was a Wednesday one year, it is a Thursday the following year (disregarding leap years). Both "b" and "c" increase by one for an advancement of one year (disregarding modulo effects). The expression thus increases by 6 – but remember that this is the same as subtracting 1 mod 7. To subtract by 1 is exactly what is required for a normal year – since the weekday slips one day forward we should compensate one day less to arrive at the correct weekday (i.e. Sunday). For a leap year, "b" becomes 0 and 2"b" thus is 0 instead of 8 – which under mod 7, is another subtraction by 1 – i.e., a total subtraction by 2, as the weekdays after the leap day that year slide forward by two days.


title: Date of Easter

text: The expression 6"d" works the same way. Increasing "d" by some number "y" indicates that the full moon occurs y days later this year, and hence we should compensate y days less. Adding 6"d" is mod 7 the same as subtracting "d", which is the desired operation. Thus, again, we do subtraction by adding under modulo arithmetic. In total, the variable "e" contains the step from the day after the day of the full moon to the nearest following Sunday, between 0 and 6 days ahead. The constant "N" provides the starting point for the calculations for each century and depends on where 1 January, year 1 was implicitly located when the Gregorian calendar was constructed.


title: Date of Easter

text: The expression can yield offsets in the range 0 to 35 pointing to possible Easter Sundays on 22 March to 26 April. For reasons of historical compatibility, all offsets of 35 and some of 34 are subtracted by 7, jumping one Sunday back to the day of the full moon (in effect using a negative "e" of −1). This means that 26 April is never Easter Sunday and that 19 April is overrepresented. These latter corrections are for historical reasons only and have nothing to do with the mathematical algorithm. The offset of 34 is adjusted if (and only if) "d" = 28 and "d" = 29 elsewhere in the 19-year cycle.


title: Date of Easter

text: Using the Gauss's Easter algorithm for years prior to 1583 is historically pointless since the Gregorian calendar was not utilised for determining Easter before that year. Using the algorithm far into the future is questionable, since we know nothing about how different churches will define Easter far ahead. Easter calculations are based on agreements and conventions, not on the actual celestial movements nor on indisputable facts of history.


title: Date of Easter

text: "A New York correspondent" submitted this algorithm for determining the Gregorian Easter to the journal "Nature" in 1876.


title: Date of Easter

text: In 1961 the "New Scientist" published a version of the "Nature" algorithm incorporating a few changes. The variable "g" was calculated using Gauss's 1816 correction, resulting in the elimination of variable "f". Some tidying results in the replacement of variable "o" (to which one must be added to obtain the date of Easter) with variable "p", which gives the date directly.


title: Date of Easter

text: Jean Meeus, in his book "Astronomical Algorithms" (1991, p. 69), presents the following algorithm for calculating the Julian Easter on the Julian Calendar, which is not the Gregorian Calendar used as the civil calendar throughout most of the contemporary world. To obtain the date of Eastern Orthodox Easter on the latter calendar, 13 days (as of 1900 through 2099) must be added to the Julian dates, producing the dates below, in the last row.


title: Taiwan Strait

text: The Taiwan Strait is a -wide strait separating the island of Taiwan and continental Asia. The strait is part of the South China Sea and connects to the East China Sea to the north. The narrowest part is wide.


title: Taiwan Strait

text: The Taiwan Strait is itself a subject of international dispute over its political status. As the People's Republic of China claims to enjoy "sovereignty, sovereign rights and jurisdiction over the Taiwan Strait" and regards the waterway as "internal territorial waters" instead of being international waters, this means that the Chinese government denies any foreign vessel having the freedom of navigation in the strait. This position has drawn strong objections from the United States, Australia, France and Taiwan.


title: Taiwan Strait

text: Former names of the Taiwan Strait include the or from a dated name for Taiwan; the or Fujian, from the Chinese province forming the strait's western shore; and the , a calque of the strait's name in Hokkien and Hakka.


title: Taiwan Strait

text: The Taiwan Strait is the body of water separating Fujian Province from Taiwan Island. International agreement does not define the Taiwan Strait but places its waters within the South China Sea, whose northern limit runs from Cape Fugui (the northernmost point on Taiwan Island; Fukikaku) to Niushan Island to the southernmost point of Pingtan Island and thence westward along the parallel N. to the coast of Fujian Province. The draft for a new edition of the IHO's "Limits of Oceans and Seas" does precisely define the Taiwan Strait, classifying it as part of the North Pacific Ocean. It makes the Taiwan Strait a body of water "between" the East and South China Seas and delimits it:


title: Taiwan Strait

text: The entire strait is on Asia's continental shelf. It is almost entirely less than deep, with a short ravine of that depth off the south-west coast of Taiwan. As such, there are many islands in the strait. The largest and most important islands off the Fujianese coast are Xiamen, Gulangyu, Pingtan (the "Haitan" of the IHO delineation), Kinmen, and Matsu. The first three are controlled by the People's Republic of China (PRC); the last two by the Republic Of China (ROC). Within the strait lie the Penghu or the Pescadores, also controlled by the ROC. There is a major underwater bank north of the Penghu Islands.


title: Taiwan Strait

text: All of Fujian Province's rivers except the Ting run into the Taiwan Strait. The largest two are the Min and the Jiulong.


title: Taiwan Strait

text: Historically both the People's Republic of China (PRC) and the Republic of China (ROC) on Taiwan espoused a One-China Policy that considered the strait part of the exclusive economic zone of a single "China". In practice, a maritime border of control exists along the median line down the strait. The median line was defined in 1955 by US Air Force General Benjamin O. Davis Jr. who drew a line down the middle of the strait, the US then pressured both sides into entering into a tacit agreement not to cross the median line. The PRC did not cross the median line until 1999, however following the first encroachment in 1999 Chinese aircraft have encroached over the median line with increasing regularity. The median line is also known as the Davis line.


title: Taiwan Strait

text: Each year, Taiwan's rivers carry up to 370 million tons of sediments into the sea, including 60 to 150 million tons deposited into the Taiwan Strait. During the past ten thousand years, 600 billion tons of riverine sediments have been deposited in the Taiwan Strait, locally forming a lobe up to 40 m thick in the southern part of the Taiwan Strait.


title: Taiwan Strait

text: The Strait mostly separated the Han culture of the Chinese mainland from Taiwan Island's aborigines for millennia, although the Hakka and Hoklo traded and migrated across it. European explorers, principally the Spanish and Dutch, also took advantage of the strait to establish forward bases for trade with the mainland during the Ming; the bases were also used for raiding both the Chinese coast and the trading ships of rival countries.


title: Taiwan Strait

text: Widespread Chinese migration across the strait began in the late Ming. During the Qing conquest, Zheng Chenggong (Koxinga) expelled the Dutch and established the Kingdom of Tungning in 1661, planning to launch a reconquest of the mainland in the name of the Southern Ming branches of the old imperial dynasty. Dorgon and the Kangxi Emperor were able to consolidate their control over southern mainland China; Koxinga found himself limited to raiding across the strait. His grandson Zheng Keshuang surrendered to the Qing after his admiral lost the 1683 Battle of the Penghu Islands in the middle of the strait.


title: Taiwan Strait

text: Japan seized the Penghu Islands during the First Sino-Japanese War and gained control of Taiwan at its conclusion in 1895. Control of the eastern half of the strait was used to establish control of the southern Chinese coast during the Second World War. The strait protected Japanese bases and industry on Taiwan from Chinese attack and sabotage, but aerial warfare reached the island by 1943. The 1944 Formosa Air Battle gave the United States Pacific Fleet air supremacy from its carrier groups and Philippine bases; subsequently, bombing was continuous until Japan's surrender in 1945. The rapid advance of the Communist PLA in 1949 provoked the government's retreat across the Taiwan Strait. On 26 February 2022, China denounced the sailing of the U.S. Navy's 7th Fleet Arleigh Burke-class guided-missile destroyer USS Ralph Johnson through the Taiwan Strait as a 'provocative act'."


title: Taiwan Strait

text: Fishermen have used the strait as a fishing resource since time immemorial. In the modern world, it is the gateway used by ships of almost every kind on passage to and from nearly all the important ports in Northeast Asia. In 2020 Chinese vessels had been illegally fishing and dredging sand on the Taiwanese half of the strait.


title: John Cleese on screen and stage

text: John Cleese is an English actor, comedian, producer, screenwriter and writer. He is known for his work on screen and stage. He was a member of the comedy sketch group "Monty Python". This is a filmography of his work which consists of about 180 various roles.


title: Stenotype

text: A steno machine, stenotype machine, shorthand machine, stenograph or steno writer is a specialized chorded keyboard or typewriter used by stenographers for shorthand use. In order to pass the United States Registered Professional Reporter test, a trained court reporter or closed captioner must write speeds of approximately 180, 200, and 225 words per minute (wpm) at very high accuracy in the categories of literary, jury charge, and testimony, respectively. Some stenographers can reach 300 words per minute. The website of the California Official Court Reporters Association (COCRA) gives the official record for American English as 375 wpm.


title: Stenotype

text: The stenotype keyboard has far fewer keys than a conventional alphanumeric keyboard. Multiple keys are pressed simultaneously (known as "chording" or "stroking") to spell out whole syllables, words, and phrases with a single hand motion. This system makes realtime transcription practical for court reporting and live closed captioning. Because the keyboard does not contain all the letters of the English alphabet, letter combinations are substituted for the missing letters. There are several schools of thought on how to record various sounds, such as the StenEd, Phoenix, and Magnum Steno theories.


title: Stenotype

text: The first shorthand machine (the word "stenotype" was not used for another 80 years or more) punched a paper strip and was built in 1830 by Karl Drais, a German inventor. The first machine was made in 1863 by the Italian Antonio Michela Zucco and was in actual use from 1880 in the Italian Senate. In New York City on December 24th, 1875, John Celivergos Zachos invented a stenotype and filed patent number 175892 for type writers and phenotypic notation application. In 1879, Miles M. Bartholomew invented the shorthand machine. A French version was created by Marc Grandjean in 1909. The direct ancestor of today's stenotype was created by Ward Stone Ireland in about 1913, and the word "stenotype" was applied to his machine and its descendants sometime thereafter.


title: Stenotype

text: Most modern stenotype keyboards have more in common with computers than they do with typewriters or QWERTY computer keyboards. Most contain microprocessors, and many allow sensitivity adjustments for each individual key. They translate stenotype to the target language internally using user-specific dictionaries, and most have small display screens. They typically store a full day's work in non-volatile memory of some type, such as an SD card. These factors influence the price, along with economies of scale, as only a few thousand stenotype keyboards are sold each year. , student models, such as a Wave writer, sell for about US$1,500 and top-end models sell for approximately US$5,000. Machines that are 10 to 15 years old still resell for upward of $350.


title: Stenotype

text: The Open Steno Project has written free open-source software, including Plover, and has developed cheap open-source hardware for stenography. Plover software translates keypresses to Stenotype on any modern keyboard, with a preference given to ortholinear keyboards that have NKRO functionality.


title: Stenotype

text: Stenograph is by far the largest manufacturer of American stenotype keyboards with an estimated marketshare in excess of 90%. Their top models are the Luminex professional writer and the Wave student writer. The Stentura paper-based writers and the paperless élan writers preceded the current models. There were two other large manufacturers in the 1980s (Xscribe, with the StenoRAM line and BaronData with the Transcriptor line). Stenograph purchased both companies and discontinued their products. The current manufacturers in the U.S. include:


title: Stenotype

text: Many steno enthusiasts are making and selling keyboards designed for use with Plover, the open source steno software. Most of these keyboards range from about $100 to $200 and allow the user to use stenography on their computer through Plover. Vendors include:


title: Stenotype

text: Stenotype keys normally are made of a hard, high-luster acrylic material with no markings. The keyboard layout of the American stenotype machine is shown at the top / right.


title: Stenotype

text: In "home position", the fingers of the left hand rest along the gap between the two main rows of keys to the left of the asterisk (little finger on the "S" to forefinger on the "H" and "R"). These fingers are used to generate initial consonants. The fingers of the right hand lie in the corresponding position to the right of the asterisk (forefinger on "FR" to little finger on "TS"), and are used for final consonants. The thumbs produce the vowels.


title: Stenotype

text: The system is roughly phonetic; for example the word "cat" would be written by a single stroke expressing the initial K, the vowel A, and the final T.


title: Stenotype

text: To enter a number, a user presses the number bar at the top of the keyboard at the same time as the other keys, much like the Shift key on a QWERTY-based keyboard. The illustration shows which lettered keys correspond to which digits. Numbers can be chorded, just as letters can. They read from left to right across the keyboard. It is possible to write 137 in one stroke by pressing the number bar along with SP P, but it takes three separate strokes to write 731. Many court reporters and stenocaptioners write out numbers phonetically instead of using the number bar.


title: Stenotype

text: There are various rule sets, known as "theories", to combine letters to make different sounds; different court reporters use different theories in their work. Historically, reporters often created "briefs" (abbreviations) on-the-fly, and sometimes mixed theories, which could make it difficult for one reporter to read another reporter's notes, but current versions of theories are primarily designed for computerized translation using a standardized dictionary provided by the company that promulgates the theory, which forces reporters to stick with one theory and use only the specific combinations in that company's dictionary. However, it is not uncommon for students and reporters to add a significant number of entries to a stock dictionary, usually when creating briefs of their own.


title: Stenotype

text: Some court reporters use "scopists" to translate and edit their work. A scopist is a person who is trained in the phonetic writing system, English punctuation, and usually in legal formatting. They are especially helpful when court reporters are working so much that they do not have time to edit their own work. Both scopists and proofreaders work closely with court reporters to ensure an accurate transcript. The widespread use of realtime translation of the strokes has increased the demand for scopists to work simultaneously with the court reporter. With transcripts produced on computer-aided transcription (CAT) software, a scopist no longer needs to have any knowledge of shorthand theories, because the software converts shorthand to text in real time via a dictionary. However, it may still be helpful in some situations while scoping, as misstroked words may not translate and would appear in steno. Depending on availability of scopists and proofreaders, court reporters may use a scopist only to clean up a rough draft of their transcript, then proofread and certify the transcript themselves, or they may use neither and produce a final transcript by themselves, though this is a very time-consuming practice.


title: Stenotype

text: Steno paper has become almost obsolete with the advancement in paperless stenotype machines. When it is used, steno paper comes out of a stenotype machine at the rate of one row per chord, with the pressed letters printed out in 22 columns corresponding to the 22 keys, in the following order:


title: Stenotype

text: This is a basic chart of the letters of this machine. There are, however, different writing theories that represent some letters or sounds differently (e.g., the *F for final "v" in the chart below), and each court reporter develops personalized "briefs" and alternate ways of writing things.


title: Stenotype

text: The following example shows how steno paper coming out of the machine represents an English sentence. Notice that key combinations can have different meanings depending on context. In the first stroke of the word "example", the PL combination refers to "m". In the second stroke of the word, that same key combination refers to the two letters "pl".


title: Stenotype

text: Many words have been abbreviated: "this", "of" and "from" are chorded as "th", "f" and "fr", and "machine" and "shorthand" become "mn" and "shand" respectively.


title: Stenotype

text: There is one NCRA-approved school in all of Canada that teaches stenotype: the captioning and court reporting program at NAIT (Northern Alberta Institute of Technology). This program uses the STKPWHRAO*EUFRPBLGTSDZ keyboard layout. Graduates are trained to be court reporters, broadcast captioners, or CART providers and report a median income of $70,000 CAD between 2017 and 2020.


title: Stenotype

text: In addition to the above American Stenotype layout of STKPWHRAO*EUFRPBLGTSDZ used internationally (Ward Stone Ireland 1913), there is also a Possum Palantype system still being used in the UK.


title: Stenotype

text: Two Stenotype layouts are in use for the Italian language: Michela and Melani. The former is in use by the Italian senate.


title: Yiff

text: Yiff is a slang term used in the furry fandom to refer to pornographic content. It is considered a tongue-in-cheek term in the furry fandom. The term is also used as a way to insult members of the furry fandom, such as in the phrase "yiff in hell".


title: Yiff

text: The origin of the term is unclear. However, according to Zack Parsons, "yiff" has been in the fandom since the 1990s.


title: Yiff

text: It is also thought to originate from a role player named Foxen, who created Foxish, a constructed language invented for use during online furry roleplaying. It was originally intended as a general-purpose expression of excitement or happiness, but became conflated with the term "yipp", which carried sexual implications.


title: Yiff

text: The "" episode Fur and Loathing, which aired on October 30, 2003, increased awareness of the term outside of the furry fandom. The word "yiff" would later become mainstream during the same decade from anti-furry hate on various sites like 4chan.


title: Neopets

text: Neopets is a virtual pet website. Users can own virtual pets ("Neopets") and buy virtual items for them using one of two virtual currencies. One currency, called Neopoints, can be earned within the site, and the other, Neocash, can either be purchased with real-world money, or won by chance in-game.


title: Neopets

text: The website was launched by Adam Powell and Donna Williams in late 1999. Two years later, a consortium of investors led by Doug Dohring bought a controlling interest in the company and in June 2005, Viacom (the company that owns Nickelodeon) bought Neopets Inc. for US$160 million. On 17 March 2014, Viacom and Nickelodeon sold "Neopets" to JumpStart Games for an undisclosed amount. On 3 July 2017, Chinese company NetDragon acquired JumpStart.


title: Neopets

text: "Neopets" allows users to create and care for digital pets called "Neopets" and explore the virtual world of Neopia. There is no set objective for the users, but they are expected to feed and care for their Neopets when they grow hungry or ill. Neopets will not die if neglected, but their health can limit their gameplay. Neopets come in a variety of species and colors and users can create or adopt their own. Users can obtain items to interact with their Neopet, such as books to read and toys to play with them. Neopets can be customised with certain clothing items, paintbrushes, morphing potions, and accessories. Neopets themselves can have pets of their own called Petpets. Users can build a customisable Neohome for their Neopets and furnish it with furniture, wallpaper, and flooring. Neopets can battle against other Neopets or non-player characters in the Battledome but they cannot die there.


title: Neopets

text: Neopia is a virtual planet with fantasy lands inhabited by Neopets and other virtual creatures. Each land has a different theme, such as pirates or prehistory, and their own shops, games, and attractions. Neopia follows its own calendar and time zone, which runs concurrent with real-world Pacific Time, and has tie-ins with certain real-world holidays such as Halloween and Christmas. It has its own economy and stock market based on Neopoints. Users can earn Neopoints through various means including playing games and selling items, which can be invested or used to buy various virtual goods and services.


title: Neopets

text: The site is regularly updated with features like new games, items, and content. Occasionally, the Neopets team release interactive storylines to expand the in-universe lore. In addition to the site content updated by the Neopets team, users also contribute content to the site. User contributions come in the form of prescreened submissions and readily editable content that is automatically filtered, such as the site's weekly electronic newspaper "The Neopian Times". There are different types of submissions that will be accepted.


title: Neopets

text: Users can earn Neopoints from playing games. Games come in many different genres, which include action, puzzles, and luck & chance. Most games have set maximum earnings or playtime. Players may also earn trophies and other awards from games if they score high enough or perform better than other users. Many single-player and multiplayer browser games are available. Users can also participate in contests and spotlights judged by staff to showcase the users' talents. Quests to retrieve items may also be performed for specific NPCs. Challenges may be made against other players or random players in a "World Challenge" for a prize piece and Neopoints from the jackpot for certain web games. Monthly competitions also exist for multiplayer games with four week-long elimination rounds.


title: Neopets

text: The economy is based on Neopoints. Users can also exchange real money for Neocash, used exclusively for the NC Mall. Users can earn Neopoints through playing games, selling items, and other transactions. Once earned, they can be saved in the bank, used to buy items from other users or non-player character (NPC) shops, used to buy and sell stocks in the Neopian stock market called the NEODAQ (a parody of the NASDAQ), or used to buy various other things. Items can be bought from shops found throughout the world of Neopia that are run by NPCs who may allow bargaining. Users can open their own shops to sell items, sometimes after obtaining those items at a lower price from sources such as other shops or charities. Items may also be exchanged through trading or auctions.


title: Neopets

text: "Neopets" has a community for users to chat with and contact other users. Each user has their own profile they can edit with HTML and CSS and are represented by avatars provided by the website, as users cannot upload their own. Most avatars must be "unlocked" by completing certain in-game tasks, such as winning a contest or getting a high score on a game.


title: Neopets

text: Users may request other users to be "Neofriends" or block other users from contacting them. To comply with COPPA, users under 13 years of age cannot access any of the site's communication features without sending in parental consent via fax. The main features include:


title: Neopets

text: Discussions through these features are restricted and may not involve topics such as dating and romance or controversial topics like politics and religion. Continuous moderation is performed by paid "Neopets" staff members, and users can help moderate the site by reporting messages they believe are inappropriate or offensive. Messages are also automatically filtered to prevent users from posting messages with profanity or lewd content.


title: Neopets

text: "Neopets" was conceived in 1997 by Adam Powell, a British student at the University of Nottingham at the time. He shared this idea with Donna Williams and the two started work on the site in September 1999, with Powell responsible for the programming and the database and Williams the web design and art. Their original office was located in Guildford. With the help of two friends, the site launched on 15 November 1999. Powell stated that the original goal was to "keep university students entertained, and possibly make some cash from banner advertising". The site contained popular culture references, such as a Neopet that was simply a picture of Bruce Forsyth.


title: Neopets

text: The user base grew by word of mouth and by Christmas 1999, "Neopets" was logging 600,000 page views daily and sought investors to cover the high cost of running the site. Later in the month, American businessman Doug Dohring was introduced to the creators of the site and, along with other investors, bought a majority share in January of the following year. Dohring founded Neopets, Inc. in February 2000 and began business on 28 April. Dohring used Scientology's Org Board to manage the company. Adam and Donna were unaware of the Scientology connections until googling the employees at the newly formed company six months later but did not address this until the company hired a woman to introduce Scientology to "Neopets". Adam and Donna stopped the addition of any Scientology education to "Neopets" and ensured such content never made it into anything site-related.


title: Neopets

text: With the new company, intellectual property that did not belong to "Neopets" was removed but the site kept the British spellings. The website made money from the first paying customers using an advertising method trademarked as "immersive advertising" and touted as "an evolutionary step forward in the traditional marketing practice of product placement" in television and film. In 2004, "Neopets" released a premium version and started showing advertisements on the basic site that were not shown to premium members.


title: Neopets

text: Viacom, the American conglomerate that owns Nickelodeon, purchased Neopets, Inc. on 20 June 2005 for $160 million and announced plans to focus more on the use of banner ads over the site's existing immersive advertising. Adam Powell and Donna Williams left Neopets, Inc. shortly after the purchase due to creative differences. The website was redesigned on 27 April 2007 and included changes to the user interface and the ability to customise Neopets. In June, Viacom promoted "Neopets" through minishows on its Nickelodeon channel. Promotions included the second Altador Cup and led to an increase in traffic through the site. The first Altador Cup was released as an international online gaming event to coincide with the 2006 FIFA World Cup to improve interactivity between users and had 10.4 million participants the first year. On 17 July, the NC Mall was launched in a partnership with Korean gaming company Nexon Corporation. It allowed users to use real money to purchase Neocash to buy exclusive virtual items. On 17 June 2008, Viacom formed the Nickelodeon Kids & Family Virtual Worlds Group to "encompass all paid and subscription gaming initiatives across all relevant platforms", including "Neopets". By June 2011, "Neopets" announced that the website had logged 1 trillion page views since its creation.


title: Neopets

text: In July 2009, the "Neopets" site was the target of an identity theft hacking scheme that attempted to trick users into clicking a link that would allow them to gain items or Neopoints. Upon doing so, malware was installed onto the user's computer. According to reports, the hack was aimed not at child players' "Neopets" accounts, but at using the malware to steal the financial data and identities of their parents. Viacom stated that it was investigating the issue, and that the hack was a version of social engineering rather than an "indictment of Neopets security practices". In an on-site newsletter for players, "Neopets" denied the report and claimed that the site's security measures prevented the posting of such links.


title: Neopets

text: JumpStart Games acquired Neopets from Viacom in March 2014. Server migration began in September. JumpStart-owned Neopets was immediately characterized by glitches and site lag. On 6 March 2015, much of the Neopets Team remaining from Viacom were laid off. Then-CEO of JumpStart David Lord assured the community that there were no plans to shut down Neopets and instead, resources were allocated to develop new content and address improve lag and site stability with plans to expand to other platforms including mobile and Facebook. The Neopets team started developing in-universe plots again in 2017 for the first time since the JumpStart acquisition. On 3 July 2017, Chinese company NetDragon acquired JumpStart Games. With the support for Adobe Flash ending in 2020, the Neopets Team announced in 2019 that it planned to transition Flash elements of the site to HTML5 by the end of 2020. The team prioritized popular features and some parts of the site are not functional. The Neopets Team also started working on developing a mobile-friendly version of the site as well as a mobile app.


title: Neopets

text: During the weekend of 27–28 June 2015, the site's chat filters stopped working. The site's forums were flooded with age-inappropriate messages. In a statement on Facebook, JumpStart apologized, explaining that the issue was due to a "facility move," and that during that move, the moderation team was not able to access the Neopets community.


title: Neopets

text: In 2016, Motherboard reported that the account information of an alleged 70 million of Neopets accounts had been compromised. The hack contained usernames, passwords, email addresses, birth dates, gender, and country from 2012 (prior to JumpStart's acquisition), but did not contain credit card information or physical addresses. Neopets responded by posting about the leak on their official Facebook page and sent emails out to all affected players telling them to change their passwords.


title: Neopets

text: On September 22, 2021, the Neopets Metaverse Collection NFT was revealed in collaboration with JumpStart, Cherrypicks, and Moonvault. Users could purchase NMC tokens on the Neopets Metaverse Collection website from November 12, 2021 ― November 15, 2021 that could then be exchanged for a randomly generated Neopet NFT on the Solana blockchain from November 15, 2021 - November 18, 2021. 4,233 NMC tokens were sold for a total of 8,708 SOLs which resulted in 4225 pieces minted for the genesis collection. Shortly after the project was announced a unique visual glitch (certain attributes were layered and colored incorrectly) revealed that at least one of images used for promotion on the Neopets Metaverse Collection website was generated using the Dress to Impress fan site, the Neopets Metaverse team replaced the image in question shortly after it was noticed and haven't responded to allegations they used Dress to Impress to generate the entire NFT collection. The Neopets Metaverse project has received a significant amount of criticism from within the Neopets community, citing general concerns about NFTs, as well as details specific to the Neopets Metaverse.


title: Neopets

text: On July 20, 2022, Neopets confirmed that it had suffered a data breach the day prior. The data breach exposed Neopets' entire database schema, including usernames, emails and passwords of its 69 million users. Neopets responded by forcing a password reset for all users on August 1, 2022, causing some players to be locked out as they no longer had access to the e-mail addresses linked to their accounts. On August 29, 2022 Neopets sent an e-mail to users detailing the results of their subsequent investigation, noting that the following information for past and present users was compromised: name, email address, username, date of birth, gender, IP address, Neopets PIN, hashed password, as well as data about a player’s pet, game play, and other information provided to Neopets. They also stated that non-hashed, but inactive, passwords for players that played prior to 2015 were accessed and potentially downloaded between January 3-February 5, 2021, or July 16-19, 2022.


title: Neopets

text: Described as an online cross of "Pokémon" and "Tamagotchi", "Neopets" has received both praise and criticism. It has been praised for having educational content. Children can learn HTML to edit their own pages. They can also learn how to handle money by participating in the economy. Reviews from About.com and MMO Hut considered the multitude of possible activities a positive aspect. Most of the users are female, higher than in other massively multiplayer online games (MMOGs) but equivalent to social-networking-driven communities. Lucy Bradshaw, a vice president of Electronic Arts, attributes the popularity among girls to the openness of the site and said, "Games that have a tendency to satisfy on more than one dimension have a tendency to have a broader appeal and attract girls".


title: Neopets

text: Luck & chance games draw criticism from parents as they introduce children to gambling. In Australia, a cross-promotion with McDonald's led to controversy with "Neopets"' luck/chance games in October 2004. Australian tabloid television show "Today Tonight" featured a nine-year-old boy who claimed the site requires one to gamble in order to earn enough Neopoints to feed one's Neopet or else it would be sent to the pound. While gambling is not required, nor are pets sent to the pound if unfed, the website includes games of chance based on real games such as blackjack and lottery scratchcards. After this incident, "Neopets" prohibited users under the age of 13 from playing Neopets's casino-style games.


title: Neopets

text: In the 2000s, "Neopets" was consistently noted as one of the "stickiest" sites for children's entertainment. Stickiness is a measure of the average amount of time spent on a website. A press release from "Neopets" in 2001 stated that Neopets.com led in site "stickiness" in May and June, with the average user spending 117 minutes a week. "Neopets" also led in the average number of hours spent per user per month in December 2003 with an average of 4 hours and 47 minutes. A 2004 article stated that Nielsen//NetRatings reported that people were spending around three hours a month on "Neopets", more than any other site in its Nielsen category. By May 2005, a "Neopets"-affiliated video game producer cited about 35 million unique users, 11 million unique IP addresses per month, and 4 billion web page views per month. This producer also described 20% of the users as 18 or older, with the median of the remaining 80% at about 14. "Neopets" was consistently ranked among the top ten "stickiest" sites by both Nielsen//NetRatings and comScore Media Metrix in 2005 and 2006. According to Nielsen//NetRatings, in 2007, "Neopets" lost about 15% of its audience over the previous year. In February 2008, comScore ranked it as the stickiest kids entertainment site with the average user spending 2 hours and 45 minutes per month.


title: Neopets

text: In January 2017, Neopets then-JumpStart CEO David Lord estimated 100,000 active daily users. In January 2020, Neopets only logged 3.4 million views per month, a significant decline from its peak. In June 2020, JumpStart CEO Jim Czulewicz estimated Neopets had 100,000 daily active users and 1.5 million monthly active players.


title: Neopets

text: Immersive advertising is a trademarked term for the way "Neopets" displayed advertisements to generate profit after Doug Dohring bought the site. Unlike pop-up and banner ads, immersive ads integrate advertisements into the site's content in interactive forms, including games and items. Players could earn Neopoints from them by playing advergames and taking part in online marketing surveys. Prior to the arrival of the NC Mall, it contributed to 60% of the revenue from the site with paying Fortune 1000 companies including Disney, General Mills, and McDonald's.


title: Neopets

text: It was a contentious issue with the site with regard to the ethics of marketing to children. It drew criticism from parents, psychologists, and consumer advocates who argued that children may not know that they are being advertised to, as it blurred the line between site content and advertisement. Children under eight had difficulty recognizing ads and half a million of the 25 million users were under the age of eight in 2005. Dohring responded to such criticism stating that of the 40 percent of users twelve and younger, very few were seven or eight years old and that preschoolers were not their target audience.


title: Neopets

text: Others criticised the functionality of the site. Susan Linn, another psychologist and author of "Consuming Kids: The Hostile Takeover of Childhood" considered the purpose of this site was to keep children in front of advertisements. Kalle Lasn, editor-in-chief and co-founder of "Adbusters" magazine, said the site encouraged kids to spend hours in front of a screen and recruited them to consumerism. "Neopets" executives stated that paid content comprised less than 1% of the site's total content. Children were not required to play or use sponsor games and items, and all ads were marked as such.


title: Neopets

text: The popularity of "Neopets" spawned real-world merchandise including clothing, jewelry, stickers, books, cereals, video games and more, sold at mainstream outlets and online retailers. The most common items were plushies (stuffed animals). Each piece of merchandise has a code which can be redeemed at the site for an in-game reward. "Neopets, Inc." had always planned to "bring the online and offline worlds together in ways that have never been done before". An investment banker at Allen & Company in New York said that "Neopets" was the only online media he had seen "that might have the ability to capture market share in the offline world".


title: Neopets

text: Neopets, Inc. signed various licensing deals with companies such as Viacom Consumer Products, Thinkway Toys, and Jakks Pacific over the years. Wizards of the Coast released the "Neopets Trading Card Game" in September 2003, which was promoted in three of General Mills "Big G" cereals and ten Simon Property Group malls. It received two different nominations for "Toy of the Year" as well as other recognitions. "Neopets: The Official Magazine" was a bi-monthly magazine released the same month but it was replaced in 2008 by "Beckett Plushie Pals", which featured "Neopets" news as well as other companies' products such as Webkinz.


title: Neopets

text: In 2005, "Neopets" expanded to film and video game deals. The first movie was to be written by Rob Lieber and produced by Dylan Sellers and John A. Davis for Warner Bros., but the project has since been cancelled with no other projects announced. Two video games were released by Sony Computer Entertainment, "" for the PlayStation 2 in 2005 and "" for the PlayStation Portable in 2006. 2006 also saw the release of "Neopets" mobile, which allowed users to visit the new land of Lutari Island, but it was discontinued on 30 June 2009, leaving the island completely inaccessible. In 2007, MumboJumbo developed a match-3 game "Neopets: Codestone Quest". "Neopets" wouldn't attempt another mobile game until 2015, when they released a match-3 game called "Ghoul Catchers" for Android and iOS. However, they still released other games during those years, including "Treasure Keepers" for Facebook and "Puzzle Adventure" for Nintendo DS, Wii, and PC. In early 2019, Jumpstart announced that they were making a full mobile-friendly "Neopets" app, and it was scheduled to launch late in the summer of 2019.


title: Neopets

text: On 10 February 2020, Blue Ant Media's Beach House Pictures announced that a "Neopets" animated television series is in development and was set to air in 2021, though there have been no recent updates. Neopets plans to expand to the Nintendo Switch.


title: Jason Orange

text: Jason Thomas Orange (born 10 July 1970) is an English former singer, dancer and actor, known for being a member of Take That. He departed from the group in September 2014.


title: Jason Orange

text: Jason Thomas Orange was born on 10 July 1970 in Manchester, Lancashire to Tony and Jenny Orange a few minutes before his twin brother Justin. He attended South Trafford College for two years beginning in 2001 and studied A-level English, and an access course including psychology, biology and history though he did not progress on to higher education.


title: Jason Orange

text: He was part of the Manchester-based breakdance crew Street Machine in the mid 1980s. They won the Manchester round of the UK Breakdancing Championship in 1985. He also appeared in the show "The Hit Man and Her" as one of the featured dancers on the show (and in a duo called Look Twice) in the late 1980s.


title: Jason Orange

text: Orange joined the boy band Take That in September 1989 and stayed with the group until their hiatus in February 1996.


title: Jason Orange

text: In 2005, Take That reformed as a four-piece and released a new greatest hits album, followed in 2006 by their first studio album since 1995, "Beautiful World". Orange contributed both songwriting and lead vocals on the album. In 2008, they released another studio album, "The Circus." In 2010, the album "Progress" was released by the band as a five-piece.


title: Jason Orange

text: On 24 September 2014, it was announced that Orange had left Take That, stating that he did not wish to continue recording music and touring.


title: Jason Orange

text: Orange appeared in the 1998 Lynda La Plante television crime drama "Killer Net" in 1998, for which his appearance was a major selling point. The following year he was in the London stage production of "Gob" in 1999. He was the lead actor together with Tom Hayes in the play, which was written by Jim Kenworth, and directed by James Martin Charlton.


title: BBC Micro

text: The British Broadcasting Corporation Microcomputer System, or BBC Micro, is a series of microcomputers and associated peripherals designed and built by Acorn Computers in the 1980s for the BBC Computer Literacy Project. Designed with an emphasis on education, it was notable for its ruggedness, expandability, and the quality of its operating system. An accompanying 1982 television series, "The Computer Programme", featuring Chris Serle learning to use the machine, was broadcast on BBC2.


title: BBC Micro

text: After the Literacy Project's call for bids for a computer to accompany the TV programmes and literature, Acorn won the contract with the "Proton", a successor of its Atom computer prototyped at short notice. Renamed the BBC Micro, the system was adopted by most schools in the United Kingdom, changing Acorn's fortunes. It was also successful as a home computer in the UK, despite its high cost. Acorn later employed the machine to simulate and develop the ARM architecture.


title: BBC Micro

text: While nine models were eventually produced with the BBC brand, the phrase "BBC Micro" is usually used colloquially to refer to the first six (Model A, B, B+64, B+128, Master 128, and Master Compact); subsequent BBC models are considered part of Acorn's Archimedes series.


title: BBC Micro

text: During the early 1980s, the BBC started what became known as the "BBC Computer Literacy Project". The project was initiated partly in response to an ITV documentary series "The Mighty Micro", in which Christopher Evans of the UK's National Physical Laboratory predicted the coming microcomputer revolution and its effect on the economy, industry, and lifestyle of the United Kingdom.


title: BBC Micro

text: The BBC wanted to base its project on a microcomputer capable of performing various tasks which they could then demonstrate in the TV series "The Computer Programme". The list of topics included programming, graphics, sound and music, teletext, controlling external hardware, and artificial intelligence. It developed an ambitious specification for a BBC computer, and discussed the project with several companies including Acorn Computers, Sinclair Research, Newbury Laboratories, Tangerine Computer Systems, and Dragon Data.


title: BBC Micro

text: The introduction of a specific microcomputer to a more general computer literacy initiative was a topic of controversy, however, with criticism aimed at the BBC for promoting a specific commercial product and for going beyond the "traditional BBC pattern" of promoting existing information networks of training and education providers. Accusations were even levelled at the Department of Industry for making the BBC "an arm of Government industrial policy" and using the Computer Literacy Project as a way of "funding industry through the back door", obscuring public financial support on behalf of a government that was ostensibly opposed to subsidising industry.


title: BBC Micro

text: The Acorn team had already been working on a successor to their existing "Atom" microcomputer. Known as the "Proton", it included better graphics and a faster 2 MHz MOS Technology 6502 central processing unit. The machine was only at the design stage at the time, and the Acorn team, including Steve Furber and Sophie Wilson, had one week to build a working prototype from the sketched designs. The team worked through the night to get a working Proton together to show the BBC. Although BBC expected a computer with the Zilog Z80 CPU and CP/M operating system, not the Proton's 6502 CPU and proprietary operating system, the Proton was the only machine to match the BBC's specification; it also exceeded the specification in nearly every parameter. Based on the Proton prototype the BBC signed a contract with Acorn as early as February 1981; by June the BBC Micro's specifications and pricing were decided. As a concession to the BBC's expectation of "industry standard" compatibility with CP/M, apparently under the direction of John Coll, the Tube interface was incorporated into the design, enabling a Z80 second processor to be added. A new contract between Acorn and BBC Enterprises was agreed in 1984 for another four-year term, with other manufacturers having tendered for the deal. An Acorn representative admitted that the BBC Model B would not be competitive throughout the term of the renewed contract and that a successor would emerge.


title: BBC Micro

text: Additionally, the last bytes of the BASIC ROM (v2 and v4) include the word "Roger", which is a reference to Sophie Wilson whose name at the time was Roger Wilson.


title: BBC Micro

text: The machine was released as the BBC Microcomputer on 1 December 1981, although production problems pushed delivery of the majority of the initial run into 1982. Nicknamed "the Beeb", it was popular in the UK, especially in the educational market; about 80% of British schools had a BBC microcomputer.


title: BBC Micro

text: "BYTE" called the BBC Micro Model B "a no-compromise computer that has many uses beyond self-instruction in computer technology". It called the Tube interface "the most innovative feature" of the computer, and concluded that "although some other British microcomputers offer more features for a given price, none of them surpass the BBC ... in terms of versatility and expansion capability". As with Sinclair Research's ZX Spectrum and Commodore International's Commodore 64, both released the following year, in 1982, demand greatly exceeded supply. For some months, there were long delays before customers received the machines they had ordered.


title: BBC Micro

text: The involvement of the BBC in microcomputing also initiated tentative plans by the independent television companies of the ITV network to introduce their own initiative and rival computing system, with a CP/M-based system proposed by Transam Computers under consideration for such an initiative by the Independent Television Companies Association at a late 1983 meeting. The proposed machine would have been priced at £399, matching that of the BBC Model B, and was reported as offering 64 KB of RAM, a disc interface, and serial and parallel interfaces, itself being a "low-cost development" of an existing machine, the Transam Tuscan, which included dual floppy drives and cost £1,700. This proposal was voted down by the ITV companies citing a possible contravention of the companies' obligations under broadcasting regulations prohibiting sponsorship, along with concerns about a conflict of interest with advertisers of computer products. Despite denials of involvement with ITV from Prism Microproducts, the company had already been pursuing a joint venture with Transam on a product rumoured to be under consideration by the broadcasting group. This product, a business system subsequently known as the Wren, had reportedly been positioned as such an "ITV Micro" towards the end of 1983, also to be offered in a home variant with ORACLE teletext reception capabilities. However, not all ITV franchise holders were equally enthusiastic about scheduling programmes related to microcomputing or about pursuing a computer retailing strategy.


title: BBC Micro

text: Efforts were made to market the machine in the United States and West Germany. By October 1983, the US operation reported that American schools had placed orders with it totalling . In one deployment in Lowell, Massachusetts valued at $177,000, 138 BBC Micros were installed in eight of the 27 schools in the city, with the computer's networking capabilities, educational credentials, and the availability of software with "high education quality" accompanied by "useful lesson plans and workbooks" all given as reasons for selecting Acorn's machine in preference to the competition from IBM, Apple and Commodore. Another deployment in Phoenix, Arizona valued at $174,697 saw 175 BBC Micros installed, with the local Acorn dealer predicting sales worth in the following two years, split between 85 to 90 percent in education and the remainder in small business. In early 1984, Acorn claimed a US network of more than 1,000 dealers.


title: BBC Micro

text: In October 1984, while preparing a major expansion of its US dealer network, Acorn claimed sales of 85 per cent of the computers in British schools, and delivery of 40,000 machines per month. That December, Acorn stated its intention to become the market leader in US educational computing. "The New York Times" considered the inclusion of local area networking to be of prime importance to teachers. The operation resulted in advertisements by at least one dealer in "Interface Age" magazine, but ultimately the attempt failed. The success of the machine in the UK was due largely to its acceptance as an "educational" computer – UK schools used BBC Micros to teach computer literacy, information technology skills. Acorn became more known for its computer than for its other products. Some Commonwealth countries, including India, started their own computer literacy programmes around 1984. Intending to avoid "re-inventing the wheel", such efforts adopted the BBC Micro in order to take immediate advantage of the extensive range of software already developed under the United Kingdom's own literacy initiative, proposing that software tailored for local requirements would ultimately also be developed. A clone of the BBC Micro was produced by Semiconductor Complex Limited and named the SCL Unicorn. Another Indian computer manufacturer, Hope Computers Pvt Ltd, made a BBC Micro clone called the Dolphin. Unlike the original BBC Micro, the Dolphin featured blue function keys.


title: BBC Micro

text: Production agreements were made with both SCL in India and distributor Harry Mazal in Mexico for the assembly of BBC Micro units from kits of parts, leading to full-scale manufacturing, with SCL also planning to fabricate the 6502 CPU under licence from Rockwell. According to reporting from early 1985, "several thousand Beebs a month" were being produced in India. Meanwhile, the eventual production arrangement in Mexico involved local manufacturer Datum, aiming to assemble 2000 units per month by May 1985, with the initial assembly intended to lead to the manufacture of all aspects of the machines apart from Acorn's proprietary ULA components. Such machines were intended for the Mexican and South American markets, potentially also appealing to those south-western states of the US having large Spanish-speaking populations. Ultimately, upon Acorn's withdrawal from the US in 1986, Datum would continue manufacturing at a level of 7000 to 8000 Spanish-language machines per year for the North and South American markets.


title: BBC Micro

text: The initial strategy for the BBC's computer literacy endeavour involved the marketing of the "Acorn Proton-based BBC microcomputer for less than £200". The Model A and the Model B were initially priced at £235 and £335 respectively, but increased almost immediately to £299 and £399 due to higher costs. The price of nearly £400 was roughly £1200 (€1393) in 2011 prices (or around £ today). Acorn anticipated the total sales to be around 12,000 units, but eventually more than 1.5 million BBC Micros were sold.


title: BBC Micro

text: The cost of the BBC Models was high compared to competitors such as the ZX Spectrum and the Commodore 64, and from 1983 on Acorn attempted to counter this by producing a simplified but largely compatible version intended for home use, complementing the use of the BBC Micro in schools: the 32K Acorn Electron.


title: BBC Micro

text: A key feature of the BBC Micro's design is the high-performance RAM it is equipped with. A common design note in 6502 computers of the era was to run the RAM at twice the clock rate as the CPU. This allows a separate video display controller to access memory while the CPU is busy processing the data just read. In this way, the CPU and graphics driver can share access to RAM through careful timing. This technique is used, for example, on the Apple and the early Commodore models.


title: BBC Micro

text: The BBC machine, however, was designed to run at the faster CPU speed, 2 MHz, double that of these earlier machines. In this case, bus contention is normally an issue, as there is not enough time for the CPU to access the memory during the period when the video hardware is idle. Some machines of the era accept the inherent performance hit, as is the case for the Amstrad CPC, Atari 8-bit family, and to a lesser extent the ZX Spectrum. Others, like the MSX systems, use entirely separate pools of memory for the CPU and video, slowing access between the two.


title: BBC Micro

text: Furber believed that the Acorn design should have a flat memory model and allow the CPU and video system to access the bus without interfering with each other. To do so, the RAM has to allow four million access cycles per second. Hitachi was the only company considering a DRAM that runs at that speed, the HM4816. To equip the prototype machine, the only four 4816s in the country were hand-carried by the Hitachi representative to Acorn.


title: BBC Micro

text: The National Semiconductor 81LS95 multiplexer is needed for the high memory speed. Furber recalled that competitors came to Acorn offering to replace the component with their own, but "none of them worked. And we never knew why. Which of course means we didn't know why the National Semiconductor one "did" work correctly. And a million and a half BBC Micros later it was still working and I still didn't know why". Another mystery was the 6502's data bus. The prototype BBC Micro exceeded the CPU's specifications, causing it to fail. The designers found that putting a finger on a certain place on the motherboard caused the prototype to work. Acorn put a resistor pack across the data bus, which Furber described as the engineer's finger' and again, we have no idea why it's necessary, and a million and a half machines later it's still working, so nobody asked any questions".


title: BBC Micro

text: The Model A shipped with 16 KB of user RAM, while the Model B had 32 KB. Extra ROMs can be fitted (four on the PCB or sixteen with expansion hardware) and accessed via paged memory.


title: BBC Micro

text: The machines includes three video ports, one with an RF modulator sending out a signal in the UHF band, another sending composite video suitable for connection to computer monitors, and a separate RGB video port. The separate RGB video out socket was an engineering requirement from the BBC to allow the machine to directly output a broadcast quality signal for use within television programming; it is used on episodes of "The Computer Programme" and "Making the Most of the Micro".


title: BBC Micro

text: The computer includes several input/output interfaces: serial and parallel printer ports, an 8-bit general purpose digital I/O port, a port offering four analogue inputs, a light pen input, and an expansion connector (the "1 MHz bus") that enables other hardware to be connected. An Econet network interface and a disk drive interface were available as options. All motherboards have space for the electronic components, but Econet is rarely installed.


title: BBC Micro

text: Additionally, an Acorn proprietary interface named the "Tube" allows a second processor to be added. Three models of second processor were offered by Acorn, based on the 6502, Z80 and 32016 CPUs. The Tube is used for third-party add-ons, including a Z80 board and hard disk drive from Torch that allows the BBC machine to run CP/M programs.


title: BBC Micro

text: The Tube interface allowed Acorn to use BBC Micros with ARM CPUs as software development machines when creating the Acorn Archimedes. This resulted in the ARM development kit for the BBC Micro in 1986, priced at around £4000. From 2006, a kit with an ARM7TDMI CPU running at 64 MHz, with as much as 64 MB of RAM, was released for the BBC Micro and Master, using the Tube interface to upgrade the 8-bit micros into 32-bit RISC machines. Among the software that operated on the Tube are an enhanced version of the "Elite" video game and a computer-aided design system that requires a second 6502 CPU and a 3-dimensional joystick named a "Bitstik".


title: BBC Micro

text: The Model A and the Model B are built on the same printed circuit board (PCB), and a Model A can be upgraded to a Model B. Users wishing to operate Model B software need to add the extra RAM and the user/printer MOS Technology 6522 VIA (which many games use for timers) and snip a link, a task that can be achieved without soldering. To do a full upgrade with all the external ports requires soldering the connectors to the motherboard. The original machines shipped with "OS 0.1", with later updates advertised in magazines, supplied as a clip-in integrated circuit, with the last official version being "OS 1.2". Variations in the Acorn OS exist as a result of home-made projects and modified machines can still be bought on internet auction sites such as eBay as of 2011.


title: BBC Micro

text: The BBC Model A was phased out of production with the introduction of the Acorn Electron, with chairman Chris Curry stating at the time that Acorn "would no longer promote it" (the Model A).


title: BBC Micro

text: Early BBC Micros use linear power supplies at the insistence of the BBC which, as a broadcaster, was cautious about electromagnetic interference. The supplies were unreliable, and after a few months the BBC allowed switched mode units.


title: BBC Micro

text: An apparent oversight in the manufacturing process resulted in many Model Bs producing a constant buzzing noise from the built-in speaker. This fault can be rectified partly by soldering a resistor across two pads.


title: BBC Micro

text: There are five developments of the main BBC Micro circuit board that addressed various issues through the models production, from 'Issue 1' through to 'Issue 7' with variants 5 and 6 not being released. The 1985 'BBC Microcomputer Service Manual' from Acorn documents the details of the technical changes.


title: BBC Micro

text: Two export models were developed: one for the US, with Econet and speech hardware as standard; the other for West Germany. The computer was unsuitable for the Australian market because, Furber said, the design failed above . Export models are fitted with radio frequency shielding as required by the respective countries. From June 1983 the name was always spelled out completely – "British Broadcasting Corporation Microcomputer System" – to avoid confusion with Brown, Boveri & Cie in international markets, after warnings from the Swiss multinational not to market the computer with the BBC label in West Germany, thus forcing Acorn to relabel "hundreds of machines" to comply with these demands.


title: BBC Micro

text: US models include the BASIC III ROM chip, modified to accept the American spelling of codice_1, but the height of the graphics display was reduced to 200 scan lines to suit NTSC TVs, severely affecting applications written for British computers. After the failed US marketing campaign the unwanted machines were remanufactured for the British market and sold, resulting in a third 'UK export' variant.


title: BBC Micro

text: In October 1984, the Acorn Business Computer (ABC)/Acorn Cambridge Workstation range of machines was announced, based primarily on BBC hardware.


title: BBC Micro

text: In mid-1985, Acorn introduced the Model B+ which increased the total RAM to 64 KB. This had a modest market impact and received a rather unsympathetic reception, with one reviewer's assessment being that the machine was "18 months too late" and that it "must be seen as a stop gap", and others criticising the elevated price of £500 (compared to the £400 of the original Model B) in the face of significantly cheaper competition providing as much or even twice as much memory. The extra RAM in the Model B+ is assigned as two blocks, a block of 20 KB dedicated solely for screen display (so-called shadow RAM) and a block of 12 KB of special sideways RAM. The B+128, introduced towards the end of 1985, comes with an additional 64 KB (4 × 16 KB sideways RAM banks) to give a total RAM of 128 KB.


title: BBC Micro

text: The B+ is incapable of operating some original BBC B programs and games, such as the very popular "Castle Quest". A particular problem is the replacement of the Intel 8271 floppy-disk controller with the Western Digital 1770: not only was the new controller mapped to different addresses, it is fundamentally incompatible and the 8271 emulators that existed were necessarily imperfect for all but basic operation. Software that use copy protection techniques involving direct access to the controller do not operate on the new system. Acorn attempted to alleviate this, starting with version 2.20 of the 1770 DFS, via an 8271-backward- compatible ++ option.


title: BBC Micro

text: There is also a long-running problem late in the B/B+'s commercial life infamous amongst B+ owners, when Superior Software released "Repton Infinity," which did not run on the B+. A series of unsuccessful replacements were issued before one compatible with both was finally released.