Which is more durable: Hard shell or soft shell?

Question: From my experience, I've only ever used hard shells simply because I've always thought they were made for more treacherous weather. However, I recently saw a video by Patagonia that claimed soft shells are more durable. Is this true? If so, why is it that hard shells are advised over soft shells for harsher weather then?
Comment: I've heard the term softshell before, but not hardshell, except for suitcases.
Comment: Interesting, but I first hear the terms softshell and hardshell. In Poland they have no counterpart, jackets are classified by membrane type. The membrane is the active element, and the durability (I think you mean water-proofness) depends practically fully on it.
Comment: In US outdoor industry, "hardshell" jackets are ones with heavy nylon outer layers, while "softshells" have either cloth or polar fleece material as the outer layer.  While there are some "gortex" softshells out there, most of the time if you say "gortex jacket" you mean a hardshell.
Comment: First thing I thought of was tacos. Guess I'll go have some dinner and revisit this question later. :)
Answer: First off - whether one is more durable or not, they're somewhat different products.  Whether you need one or the other is more based on what you're doing than on "durability".
Hardshell vs Softshell
note - these are marketing terms in the US outdoor industry.  Apparently they're not standard internationally.
Hard shell jackets offer a high level of windproofing, and low breathability. They're also usually the most waterproof.  They're made with heavy nylon / canvas materials.  Think a heavy gortex rain jacket.  The hardshell material itself offers great protection against wind and rain, but not much insulation.  Because they're windproof, they usually don't breath as much as softshells.
Softshells are more like polar fleece jackets, perhaps with a cloth cover- they're very warm, because the material traps a lot of air.  They also tend to retain their warmth when wet.  Some softshells may have a goretex treatment, and be somewhat waterproof.  But they're generally not very windproof.
What they're for
Hardshells are necessary for harsh environments with strong winds.  You may also have a "softshell" jacket underneath the "hardshell" outer layer for insulation.
Durability
Durability in outdoor gear is a odd issue.  My experience is that a lot of gear on the market now is designed to be ultra lightweight, often at the expense of durability.  Jackets, backpacks, even the expensive ones just get torn up sometimes.  You can find products with more rugged construction, but they come at a weight penalty.  I could see how a serious mountaineer (which high end jackets are theoretically designed for) may prefer a light outer layer that will just get replaced after each expedition.
Comment: I realize I didn't exactly answer the question... but I feel like hardshells and softshells are for different things, and they're both valuable.  Its like asking "which is more durable, a seat belt or my car's airbags?"
Answer: The hardshell/softshell distinction doesn't mean pretty much anything today. It used to be that hardshell was completely waterproof and windproof, implying limited breathability, and softshell was somewhat waterproof, somewhat windproof and much more breathable. In other words, softshell used to mean a material you could wear most of the time while being more comfortable than wearing hardshell.
Then some of the outdoor manufacturers unfortunately realized that those softshell things sell quite well and reused the label for whatever they wanted to sell. Nowadays the softshell label can mean almost anything, so that it doesn't make sense to say if it's more durable than hardshell. (Especially given that the waterproof and windproof "hardshells" are today often built to minimum weight, so that the toughness greatly varies between different hardshells even within one brand.)
Comment: +1 - that's right.  Whenever you're buying an expensive piece, these days, you really have to research the fabric itself.  Even "Gortex" (the biggest jacket material brand name in the USA) is really a label applied to a half dozen different fabrics with slightly different properties.


How many enemies of each type in Spartan Ops missions

Question: I am trying to work on commendations.  This would be accelerated if I knew the headcount of each enemy type in a given game.  Then I could focus on missions to grind each commendation to completion.
Comment: I don't know each mission's headcount, but I do know that there are a lot of Hunters in Episode 3, Chapter 4.
Answer: We can probably limit our search somewhat, since there are some "obviously better" spots to farm.  Here's my hit list of best Spartan Ops (only the first 3 episodes have been released, so this might need updating later...)  For the purposes of this, I've played the op on Normal, solo, and killed any allied units that might steal kills.  There may be some variance in the enemy types depending on the difficulty, but the time invested in playing Heroic/Legendary vs the XP/kills is probably not worth it.
Prometheans
For Prometheans, the "overall best" is currently E2C5 (Gagarin).  On this op, there are:

40 Crawlers
3 Crawler Snipers
55 Crawler Primes
16 Knights
3 Knight Battlewagons
1 Knight Commander
8 Watchers

This one is made easier by the fact that there are incineration cannons on a rack on the second story of the central area.  There's also a lot of shotguns and shotgun ammo, which on Normal will kill a Knight pretty quickly.
I believe there are more Watchers on E2C1 (Cleanup), but it takes a while to get to them so I wouldn't suggest farming Watchers here unless you've also got some Covenant enemies to farm.
Covenant
For Covenant, there are a couple of good ones.  The one that I prefer to run is E3C4 (Shootout In Valhalla, aka "the Mantis one"), which has:

27 Grunts
17 Grunt Imperials
0 Grunt Ultras
24 Jackals
4 Jackal Majors
11 Jackal Rangers
32 Elites
0 Elite Zealots
19 Elite Officers
2 Elite Generals
12 Hunters
0 Ghosts
26 Banshees
1 Wraith

Halfway through, you'll gain a Mantis, and it will respawn if it is destroyed, as many times as you need it.  Killing a Banshee also gives you credit for an elite, and they're pretty easy to down in a Mantis.
The Hunter count and the Banshee count are pretty insane.  You'll note there's no Grunt Ultras, Elite Zealots or Ghosts on this map though.  (Well, unless the Elites steal your Ghost...)
If you want some Grunt Ultras in your Spartan Ops, you might try E3C1 (The VIP, aka "the Scorpion one"):

28 Grunts
24 Grunt Imperials
7 Grunt Ultras
1 Jackal
5 Jackal Majors
25 Jackal Rangers
20 Elites
1 Elite Zealot
12 Elite Officers
7 Elite Generals
0 Hunters
0 Ghosts
0 Banshees
4 Wraith

About halfway through this level, you'll get another vehicle (TANK!) that respawns if it is destroyed.  It's pretty easy to lay waste to everything with the tank.  Even the early part is pretty easy, as after the first wave you'll get a drop of power weapons that make taking the hill fairly trivial.
We're still kind of low on Elite Zealots and Jackal Majors, so consider E3C5:

31 Grunts
19 Grunt Imperials
7 Grunt Ultras
13 Jackals
17 Jackal Majors
29 Jackal Rangers
3 Elites
14 Elite Zealots
1 Elite Officer
2 Elite Generals
2 Hunters
0 Ghosts
0 Banshees
0 Wraiths

NOTE:  Playing this on normal significantly increases grunt ultras.  There will be at least 11 before the second phase of the mission.  So bear in mind if you are finished with the others and want to focus on ultras.
This one goes a lot slower, as there's not an abundance of vehicles or power weapons.  I'd almost consider waiting it out for another Op that is somewhat easier and contains the enemies you need.
Other Notes
There's not a lot of Ghosts in my suggested hit list.  There are some on E1C1 (Land Grab, includes multiple empty wraiths, ghosts, and one of each warthog), although there's a lot of dead space in that one and farming them solo's not great.  Beyond that, killing Ghosts in War Games also counts towards this commendation, so you could also get progress by playing something like Big Team Slayer.
If I've got to farm just Hunters or Ghosts (ie, for a challenge), I'd probably go for E2C3 (Hacksaw).  You can grab a rocket launcher at the beginning by sprinting straight ahead, and then there is more ammo at every location where the marines are under fire.  Around the ramp up to the central structure are always 2 Hunters and 1 Ghost.
As a side note, if you're farming a particular type of enemy, you can kill that enemy and then restart the op and still get commendation/challenge credit for the kill.
Conclusion
While I understand you may want to farm commendations for the OCD value, the XP bonuses are very limited compared to the pain involved.  I will tend to do the weekly challenges, but I don't give much time to worrying about the commendations, personally.
If you're just in it for XP, solo'ing will give you a better shot at getting a kill yourself, but you'll gain far more XP (2x or more!) by playing in a matchmade game.
Comment: Good info.  I'd like to add that Elite Zealots are best farmed in Episode 3 Chapter 5.  All the jetpack elites count.
Comment: @HotinRhino, added the counts for E3C5.
Comment: Farming Hunters on E2C4 would probably be better than C3 (AKA "The Mantis One") Doing that solo was interesting, especially with the drop pod with 6 hunters in it landed...
Comment: @tombull89, for just Hunters, I suggest(ed) E2C3 - you can play on Easy, murder a couple of hunters with the rocket launcher, then restart the chapter and go kill them again.  If you're farming more Covenant types I still think E2C3 is superior, even in solo.  If you're getting pinned down in the Mantis, try getting further away and letting them trickle towards you.  My kills per unit time are quite a bit better with a vehicle, though YMMV.
Comment: I'll keep a watch on this as more missions become avail, but I suspect agent86 or others will similarly edit to keep it current.  In terms of the Hunter debate, Agent is correct for pure farming E2C3 works out faster, but I can't take the monotony of constant reloading.  I mean, farming is bad enough, but at least the game can buy me dinner first (i.e. give me a huge robot to mow down my enemies with).
Answer: I made a chart just for this kind of thing. Be aware that it changes slightly from game to game.
Comment: +1 for seemingly missed answer, even has been appropriately updated for Episode 6.
Comment: When this question was a little more current back around EP 3 I think Agent86's answer was the best.  Now that some time has past and you've gone to the effort of keeping it current through EP 6 I'll pass it on to you.  In truth I kind of lost interest in H4 when they had the big delay in Dec/January to continue releasing Spartan Ops episodes.  Thanks for keeping up with this!
Answer: Chapter 4 of episode 3 (Shootout in Valhalla) is the best place for Hunter farming.
Grab a Mantis, and there are 10+ even on easy.
Takes about 10 minutes for the whole mission on solo, plus gives TONS of Banshee kills.
Answer: The number of Watcher kills required to reach the next rank in commendation is ridiculous given that the most any mission has is about 15-20. Therefore, I found an easier way to farm them.
I think it's the 2nd chapter of Episode two (You start off in the Ragnarok map), create a loadout with the firepower and ammo perks, pick two precision rifles (I prefer the DMR and Light Rifle) and snipe the watcher flying around at the far base. Remember, Knights release Watchers if they are unaware of your presence. You'll get roughly 30 Watcher kills in, say, 5-6 minutes.
Once out of ammo, restart the chapter. Easy-Peasy.
Comment: Welcome to Arqade! We're a Q&A site, not a discussion forum, so I edited your answer a bit to focus on the problem the asker is facing. You can take a look at [the About page](http://www.arqade.com/about) for more info.


Which bond - C-C or C-H - is stronger?

Question: I've read that nonpolar bonds are stronger than polar bonds. If it is true, why $\ce{C-H}$ bond entalpy ($\pu{413 kJ/mol}$) is more than $\ce{C-C}$ ($\pu{348 kJ/mol}$)? I'm very confused at the moment.
Answer: The "strength" of a bond can't be evaluated just based on its enthalpy.
According to this relation
$$ \Delta H = \sum \Delta H_\text{bonds broken} - \sum \Delta H_\text{bonds created} $$
the strength of your bond will depend on the reactive nearby the bond. If the molecule is likely to create bonds with higher enthalpy after the bond's breakdown, then the enthalpy variation will be negative. The process will then be spontaneous and the initial bond will breaks "easily".
There is also some steric consideration, the hydrogen atom is smaller, the bond is then more easy to be "attacked".
Finally, for a polar bond, the electronic cloud is delocalised closer to one atom rather than the other (according to their electronegativity) so you have "less perturbation to add" to fully remove the covalent electron from the less electronegative atom.
Comment: Thanks! Could you tell me why in asymmetric alkenes the carbon with more hydrogen is more electronegative that the other?
Comment: What do you mean by "will depend on the reactive nearby the bond"? What is "reactive"? Did you mean to write something else?
Comment: Moreover, there are a few anomalies: "If "the hydrogen atom is smaller, the bond is then more easy to be "attacked"", then shouldn't its energy be **lower** instead, because other atoms are able to attack it and break the bond "easily" as you say? Similarly, "you have "less perturbation to add" to fully remove the covalent electron from the less electronegative atom." This again hints at the C-H bond (the more polar one) being weaker. Both are contrary since $\ce{C-H}$ has a higher bond enthalpy. Could you please explain? Thank you!
Answer: I disagree with the currently accepted answer, and believe that there are other reasons at play.
First of all, the difference in the electronegativities of carbon (2.55) and hydrogen (2.2) is roughly 0.35. The $\ce{C-H}$ bond is indeed slightly more polar than the $\ce{C-C}$ bond, but this slightly increased polaity can in no solely way account for the approximately 20% increase in bond energy. In fact, Wikipedia writes: "Because of this small difference in electronegativities, the C−H bond is generally regarded as being non-polar."
I believe the real reason here is atomic size. The hydrogen atom is much smaller than the carbon atom. Smaller bonds lead to higher bond energy, therefore $\ce{C-H}$ bond has higher bond enthalpy than the $\ce{C-C}$ bond.

Which bond - C-C or C-H - is stronger?


New user posts comment as answer

Question: What should I do in the First Posts, Late Answers and Low Quality Post review queues when I see that a new user has posted a comment as an answer (they don't have enough rep to post comments yet)?
Comment: You just flag it as _"Not an answer"_.
Comment: In *which* review queue?  They're all radically different in how they handle different situations.
Comment: @reggaeguitar He just guessed.  He could just as easily have guessed wrong.  His answer is either incorrect or incomplete for most of the other queues out there.  If your question was actually clear as to what you were asking about, that wouldn't be the case.
Comment: @πάνταῥεῖ That depends on what queue you're in.  For example, if you're in LQP that's very much the wrong thing to be doing.
Comment: Why the downvotes? Because I didn't specify which queue? Arun was able to provide a perfect answer to what I think is a reasonable question
Comment: Downvoting and voting to close my question about how to be a better reviewer just makes me want to not review at all, I don't understand why everyone has to be so high and mighty on this site, it's very offputting. I searched for another question to answer mine and nothing came up, I'm sure this will be helpful for people in the future as evidenced by the 9 upvotes to Arun's answer
Answer: In the First Posts and Late Answers queue, Flag it as not an answer ( and also leave a comment telling them the reasons in a nice way ).
In the Low Quality Posts queue, Recommend Deletion as "a comment posted as an answer"
Even if they are new users, they should only provide answers in Answers. We must keep Stack Overflow clean with Quality answers. Letting them post comments as answers would only encourage future readers to do the same
Comment: Although I agree that this is probably the best way of doing it, this will still be a problem as long as comments can't be either accepted or upgraded to answers. I fear that many correct comments (that do answer to question) gets overlooked since there was no accepted answer.
Comment: @DanielLarsson, rather than just posting a low quality answer that would have been better of as an answer, it would be best to add a much more detailed answer for future reference. If a comment answers the question, then it can be explained to make it suitable as an answer as well ( typo's and other small problems are exceptions, those questions should be closed instead ). So, better to post an answer with a good explanation rather than post a small comment which may be overlooked.

New user posts comment as answer


Can I set a theme-specific home page?

Question: I set up the exceptions in the Config tab to load a different theme for mobile devices and I would really love it if I could set a different home page also. I would like mobile visitors to see completely different content than desktop visitors. Is there a way to do this?
Comment: I created https://github.com/meanbee/magento-homepage-per-theme to solve this problem.
Answer: If your current theme is responsive then you can use media queries in the custom xml layout update of your home page depending on how different you want the theme to be. You might try using static blocks to display your home page content then and having a 'mobile' static block then an alternative 'desktop' static block that displays over 'X' pixel value.
If your layout is set to full width then you don't have to worry about the left or right sidebars. Otherwise just correspond your media query break to the 'no display' function of your sidebars and the mobile static block will be displayed at the same break point as your hiding of the sidebars.
Hope this helps.

Can I set a theme-specific home page?


Isolating red ink with GIMP/Photoshop

Question: As a puzzle author, I often write puzzles with red ink and then test-solve them with pencil. What would be the most efficient way to remove the pencil and blue gridlines from the paper to leave only the red puzzle clues behind?
Comment: If you did the pencil and red on different layers you could remove the whole layer at once
Comment: Sorry, I should clarify: I'm working with a scan of my actual paper notebook.
Comment: Can you attach a sample image?
Answer: For Gimp
To remove all content of a scan except red drawings we may do as follows:

Scan image in desired resolution

This image deliberately was a poor scan using a black and a red pencil to make it harder for us. Using a bright red felt pen will definitely make isolation much easier, but this probably is not what we have in reality.
Isolate red color with the Select by Color tool  with an appropriate threshold to make sure only pixels on the red lines are going to be selected (here this was 10):

Select > Grow the selection by an appropriate value (5 pixels in my case):

Select > Feather the selection for a smoother transition (here by 5 px)
Select > Invert the selection
Press Del or Edit > Clear to remove everything in the  background:
Answer: a much easier solution is to use a piece of vellum or tracing paper when you are working on the draft. Simply lay the vellum over your red areas and write on it. When you're done the vellum is not actually part of the artwork and the red can be scanned without any need for alteration.

Isolating red ink with GIMP/Photoshop


Why do some people bond with their captors and vice versa?

Question: Why do some people in hostage and/or kidnapping situations end up identifying with their captors, and vice versa?
Are there certain triggers or aspects of the situation that make it more or less likely to occur?
Answer: What you are describing is a condition popularly known as the Stockholm Syndrome. It should be noted that very little research has been conducted into this condition, and it has not been classified as a disorder. However, very briefly, Stockholm Syndrome leads to a hostage developing an emotional bond with their captor, where they sympathize with them and form positive feelings towards them.
It is believed that this syndrome is a coping mechanism (Cantor C, Price J), a result of spending intimate time with their captor where they are subjected to abuse. The captives are in an incredible amount of stress and typically lose the ability to think rationally and reasonably. Their primary motive is to survive, and this instinct leads them to develop defense mechanisms. Hatred, in this situation, would not be productive, and obedience is the only way to survive.
It is believed that 3 aspects make it more likely for the syndrome to develop:

Long duration of time spent together
Spending a longer duration of time with their captors leads the
hostages to believe that their captors truly will not kill them. They
believe that the captors are their friends and they will get out of
this messy situation together.

Intimate and continual contact between the captor and the hostage
In order to ensure that they do not anger their captor in order to escape violence at their hands, the focus of the captives is on obedience and pleasing their captors, for which they try to get to know their captors during the period of their captivity. This 'humanizes' their captors. Moreover, the captives want to make sure that their feelings do not appear fake, and eventually begin believing that they are genuine.

Small acts of kindness
During the course of the captivity, if the captor shows an unexpected
act of kindness, or simply chooses to not behave violently, it may
lead the captive to become affectionate towards their captor. In a
situation where a person is made to fear for their life, this small
act can be seen as merciful on the captor's part.

Women are said to be more likely to develop Stockholm Syndrome. (Graham, Dee L. R.) Societal conditions lead the women to be afraid of male violence. This fear encourages them to engage in actions that would please the male, and bond with them to survive. Similarly, the captives bond with their captors and attempt to please them to survive.
A lesser known condition is the Lima Syndrome, where the abductors develop sympathy towards their captives.
As mentioned in the beginning, these conditions are still widely contested and much more research is required.
Comment: Welcome and thanks for your interesting answer. We do expect answers to be accompanied by appropriate resources, preferably journal papers, or otherwise credible sources.


Is there any way to speed up city production?

Question: Is there any possibility to speed up a city production?
Answer: A few options:

The most obvious solution is to increase the production of the city. A few ways to do it are:

Build a few production-increasing buildings before you build your long building.
Purchase production-increasing buildings with gold.
Increase the production yield of the city's tiles by improving them with workers, or build factories using great engineers (though great engineers can be used in a different way, see below). Marble is especially useful, as any city which has a worker on improved marble gets a 25% production boost, though only for wonders.
Shoot for technologies or social policies that increase production. For example Steam Power increases production from lumber mills, so if you have a lot of those around your city this technology could really give it a boost; Railroad will allow you to connect cities by railroad which increases production; and the Order social policy will increase all production for building by 25%.
Redirect the civilian allocation to increase production. You can just use the radio button under the "civilian allocation focus" to let the computer choose the best allocation, or you can do it yourself manually. It means that you should put civilians inside tiles / buildings that have the most impact on production. If you're desperate for production you can de-allocate a citizen altogether: each unemployed citizen produces 1 production per turn.

Chop down trees around the city. Chopping down trees gives a small boost towards the currently in-progress building. You can even chop trees in an area outside your territory, it still gives some production (though less, and it gets further decreased with distance) to your closest city.
The great engineer can speed up buildings and wonders. When you use his ability it gives a tremendous boost to the current in-progress structure, often making it complete just one turn after you use his ability. Very powerful, don't waste it on anything which isn't worth it. Notice that if you build something ridiculously difficult it will probably not get down to 1 turn.

Note: if it's particularly the courthouse which is giving you trouble, consider getting the Police State social policy, under the Autocracy tree, which makes occupied cities produce only half the unhappiness value.
Comment: +1 impressively thorough list.  I didn't know you could chop trees outside your territory and still get bonus production.
Comment: I tried doing all of this that I could - looks like I'm going to end up just six turns short of getting my first culture victory. SO CLOSE!
Answer: Oak has a great list of the conventional methods for increasing production. There are a couple of other options you can consider, although they are more situational and involved:
Start a Golden Age

In a golden age, any tile that produces gold produces an additional gold, and any tile
  which produces production produces an additional production.

I love production I was producing producing additional production.
Golden Ages can be started using a great person, saving up enough excess happiness, and various wonders/social policies.
Play as a Civilization that Boosts Production
This is more involved than starting a Golden Age, or any of Oak's suggestion: Civilizations are chosen before the game, so you can't react in the middle of the game when you realize you need a courthouse to finish faster, and you lose the benefits of your other favorite civilization. So, I would recommend using other suggestions first, and switching Civilizations only if you find the other suggestions aren't enough.

Rome: "+25% Production bonus when constructing a building (in another city)
that already has been constructed in the Capital."
Russia: "[Strategic] Resources provide +1 Production"
Egypt: "+20% Production speed of Wonders."

Quotes from the Civilization 5 Manual.
Answer: Place cities in areas with plenty of hills and forest tiles.  In Civilization IV, food tiles were of utmost importance in allowing cities to become large and prosperous.  The introduction of maritime city-states to Civilization V, along with the decreased food output from non-strategic resources, makes food tiles a lesser concern.  Now I happily settle in the hills and forests, knowing that in the mid to late game I can maintain alliances with several maritime city states to make up for any missing food.  Besides allowing you to increase production by working mines and lumber mills, this also allows you to use specialists very liberally, which can lead to tremendous science output (with the Secularism social policy) and even more greatly increased production (if you are able to build the Statue of Liberty).
Answer: If you have a great engineer, you can expend them to complete a wonder instantly. There doesn't seem to be a way to increase production speed by spending gold, short of spending enough gold to purchase it outright (and not all units / buildings can be purchased. For example, wonders.)
Edit: As of the 12/15 patch, you can buy courthouses outright in conquered cities, which is a decent way to boost production in those places. (Though expensive!)
Comment: yeah..the Courthouse is the reason for my question :) takes about 100 Rounds in Epic Mode to build on in a conquered city.
Comment: Turns out they don't always complete the current construction project instantly - I've had a 350-turns-remaining wonder only taken down to 120 turns remaining or so :( I guess I've learned the hard way.
Comment: Oak -- Related: http://gaming.stackexchange.com/questions/9775/how-high-is-the-production-bonus-of-a-great-engineer-in-civ5


Are short usernames a security concern?

Question: I was somewhat suprised that the sysadmin approved a one-letter username like "m" and my username is also short ("nik"). I think that if usernames are brute force attacked then the username should also be longer than just a few characters. Do you agree?
Comment: Long usernames is more important to limit spamming since it is where username bruteforcing would occur. firstname.lastname@example.com may receive more spam than email@example.com, that's why some email provider require the username to be a minimum length. Apart from that, the security itself comes from the password, not the username which is a public information.
Answer: The username is not a secret; any determined attacker will be able to find out the names of users on your system.
What does improve your security, is if there is no remote access for "root", "guest", and similar account names found on many systems. In fact, Ubuntu explicitly disables the "root" account because it is such a favorite target.
Comment: Some companies enforce two-factor-authentication for remote access. This should thwart any bruteforce attempts, even if the username is known.
Answer: one-letter is indeed a bit short, but a good IDS can quickly see if someone is messing with your network if 3 letter usernames are being used.
But from a security standpoint one should assume the Username is known to an attacker since its often easy to guess or not protected at all (leaked at some other place) so short usernames are not so much an issue, when the systems have other protection mechanisms in place.
Answer: Many systems have a standardized way of generating usernames (last name first initial, email address, etc) and other systems leave usernames completely public facing (WordPress, although you can hide then via plugins). So it is common to have little or no secrecy when it comes to the choice of usernames.
This is the reason for passwords in the first place. If usernames were intended to be secret and complex then what exactly is the point of passwords? At that point you would now have two passwords.
While a 3 or 1 character username does seem a bit excessive it does not give any particular advantage to a brute force attack when used on any system that has either predictable or pubic facing usernames in the first place.
An example of a username that could/would make you a target for brute force attacks is something as common as 'root' or 'admin' because these have historically been widely used for high access accounts.
Answer: No one will going to hack you without not knowing your user name.
Your password is the one which prevents you from brute force attacks.
The spammers have a databases with email addresses and not just randomly send emails to all possible user names also.
Looks like nothing is wrong with your system administrator.
Comment: This is an unfounded assumption, You do not know what hackers 'think' or try to do. It is known that some spammers do use username prediction.

Are short usernames a security concern?


I would like to try grilling fruit - any suggestions?

Question: I had a catered lunch the other day that had grilled fruit (apples, pineapples) it was great and I wanted to try it at home.  Are there any tips as far as preparation or what to glaze them with or basic techniques?
Answer:
Usually I cut a peach in half, put a bit of salt and honey on the non skinned end, and grill it (cavity down) for a minute or two then rotate it to get good grill marks. I then add a scoop of ice cream in the cavity and sprinkle with cut fresh mint.
Another fruit I like grilled are apricots, although really put them on for 20 seconds or so.

My rule of thumb is that, if it's a harder fruit then it can be grilled, and usually it can only be grilled on the non-skin side.
Comment: The peaches this year in Ontario (and probably everywhere) have been amazing. I've been grilling them once a week or so all season.
Answer: Further to grilled pineapple.
I like to quarter it and then marinate it in a bit of rum (1 oz), a bit of lime juice (1-2 tbsp) and then generously sprinkle some brown sugar over it.
Garnish with mint.
Comment: rum *and* lime juice, that's an absolutely stellar idea, +1 for that from me.  can't wait to try it this weekend.
Comment: That sounds awesome!!
Comment: +1 for rum.  Also good to add - juice from canned pineapple reduced down to a syrup.
Answer: I love grilled pineapple myself...You can put it on skewers, and marinate it, or you can just throw slices straight on the grill. Any kind of sweet marinade will do fine. Brush it with butter and brown sugar, and throw it on a jerk chicken sammich in lieu of a tomato.
Plantains are great grilled: don't let the banana appearance fool you, they're tough enough to grill, as long as you don't slice 'em too thin. Brush 'em with a little butter and maybe some sugar if you're doing them as a desert.
Comment: I love grilled pineapple with nutella!
Answer: I'm a huge fan of grilled mango, and to be honest, I don't really do anything to it at all.  Slice it, skewer it, grill it.  The taste of a grilled mango slice is so much different than a fresh mango slice, even the picky eaters at my house liked the complexity of flavor when grilled (whether they like fresh mango or not).
In my experience, mango can get too charred very fast, so keep an eye on it.  I've seen recipes that say to cut cross-hatch marks in them, but in my experience they get too soft too fast when doing this.  I generally grill 2-3 minutes per side, with a high flame beneath them.  If they're not slightly charred around the edges by this point, I'll give them another minute per side (I leave the skin on so I can use its char level as a gauge).
Mango can be tricky to cut, here's a video to get you started if you're not familiar:
http://video.about.com/thaifood/Cutting-mangoes.htm
I agree with satanicpuppy's pineapple recommendation, I've had them marinated and just plain.  The butter/brown sugar combination is awesome!  You can also soak them in a good rum first (yum), but be forewarned, when they hit the grill you'll have quite the temporary light show, so place them using long tongs, NOT your hands.
I remember once, I had grilled pears at someone's house.  From what I remember they were just sliced and grilled, no seasoning or marinade, but I wasn't there when they were prepared so I don't have any specific recommendation there other than to give it a shot - they were delicious!
A few recipes suggest soaking the fruits in water or a lemon/water combination for 20 minutes before grilling.  The water is supposed to help the fruit stay juicy; the lemon helps it hold color.  I have tried the water technique, I didn't notice a huge difference other than I had to wait 20 more minutes to enjoy my fruit!  And since I generally grill fruit for myself, I don't really care if the color changes, but it's something to keep in mind if you're grilling for a party.
Answer: I can also recommend grilling pineapple and then adding it to a salsa with onions, lime juice, cilantro, jalapeno. Good stuff.
Answer: Bananas! I grill it as 1 piece with the skin on. When the skin gets dark it is ready.
Comment: I've never considered grilling a banana and am excited to try this tonight!


Why a pentaprism and not a simple flat mirror?

Question: I don't understand why pentaprisms are needed to reflect light from the image up through the viewfinder. When I read why it is used, the explanation seems to indicate that it ensures the light coming up is reflected out the viewfinder at 90 degrees. But wouldn't a 45-degree flat mirror accomplish the same thing?
Comment: @scottbb I saw that one but didn't get it.

"It's important to realize that you don't actually look directly through the lens with an SLR!" Aren't we though? "If you did, a periscope style arrangement would do just fine" So why not?

"What you are actually doing is looking at an image projected onto the focussing screen by the lens." Isn't this the same thing? The image we're seeing bounced up off the mirrors? "This image is flipped left/right and up/down by the lens, and then up/down again by the main mirror." What's the "main mirror" here and why is it flipped this way?
Comment: I am looking at diagrams such as https://i.stack.imgur.com/P1gz0.jpg
Comment: Even in a periscope, the incident light is still the correct orientation after bouncing off the two mirrors and I don't see why it wouldn't work the same way in a camera like the diagram above. Periscope: http://physics-igcse.weebly.com/uploads/1/3/4/3/13437876/873907750.JPG
Comment: here's a more instructive diagram: https://cdn-ep19.pressidium.com/wp-content/uploads/2019/03/Lens-4.jpg
Comment: Left-right inversion: https://upload.wikimedia.org/wikipedia/commons/thumb/3/3b/Roof-pentaprism.svg/300px-Roof-pentaprism.svg.png (Technically six sides, interestingly). I can't tell what becomes of the light rays that hit the crease though.
Comment: A periscope is typically designed with a relay lens, which extends the imaging system and flips the image just as the primary lens/system does... it's not just mirrors.
Answer: It's important to understand that the image through the lens is inverted in both the lateral (x ↔ -x) and vertical (y ↔ -y) dimensions. Mathematically, this is the same as a 180° rotation about the z-axis (optical axis).
Thus, the upright image entering the lens, after being refracted and focused, leaves the lens flipped both vertically and horizontally. In order to view the image correctly, some sort of lens or mirror arrangement will have perform an additional left-right and up-down inversion.
A periscope mirror system performs two up-down mirror inverions, leaving the output image the same as the input, meaning a periscope is merely a translation of the image, but does not transform the output image with respect to the input image.
If you used the focusing screen on an older look-down SLR (one without a pentaprism/pentamirror) or TLR camera, such as a Rolleiflex, you'd see an image that is correct top-to-bottom (i.e., the sky is at the top of the image in the focus screen), but is flipped left-right. That is because the 45° reflex mirror that aims the image vertically doesn't transform the image left-right. It essentially undoes the up-down inversion that the lens performs, leaving only the left-right lens inversion.
Thus, the image entering the pentamirror / pentaprism on top of a typical SLR or DSLR is correct top-bottom, when viewed looking down onto the focusing screen. But if you were cut a periscope in half and look down onto the first mirror, the image would be inverted top-bottom (but not left-right).
So the difference between a periscope system, and a reflex mirror in the body plus pentaprism/pentamirror to the viewfinder, is that the pentamirror includes an extra up-down inversion to produce an image that vertically correct, as compared to the periscope system, which expects a correct image entering the periscope system.
Note: In reflex cameras, the pentaprism/mirror is also a roof style mirror, that performs a single left-right inversion in the middle of all the bouncing around. Essentially, one of the reflective faces in the pentaprism/mirror system is actually not a single reflective surface, but an inside corner of a 90° angle that bounces the light laterally, as well as vertically. I guess you could say technically the prism/mirror is no longer penta-faced and more hexa-faced. But I like the existing nomenclature of roof pentaprism to denote that the main light path is inside a 5-sided polygon, with the addition/adjective of the roof feature which accomplishes a secondary goal of fixing the image in the left-right plane.
Comment: One thing none of the diagrams commented in (and none that I've seen) do well is show the left-right transformation.
Comment: Ha. Yeah. That's the bit I was missing - two mirrors WOULD accurately show you exactly what's coming out through the lens ... the problem is that the LENS is the one flipping and inverting the image first.
Answer: First you have to swap left/right from the focusing screen (a matte surface since the viewfinder needs to display a 2D image and not a 3D one or you could not figure out whether the camera is focused as your eye could accommodate to the distance).  And a pentaprism uses total reflection inside, so in contrast to the lighter pentamirrors it does not lose light for the three reflections inside.
Comment: Sorry, I don't understand this answer or how it addresses my confusion. I don't see where this left/right switch is happening or why it's happening at the focusing screen (isn't this screen blocked when we're not taking pictures anyway?). Also a pedantic counterpoint but doesn't reflection technically always lose light even if just a very small amount?
Comment: @JohnKip Yes, every time light interacts with any surface, there is loss of light intensity. That's just the nature of physics. The loss itself doesn't really matter — it's just something that happens on the way to the goal of capturing the image. It's like water wheels in a stream: very little of the energy of the moving water is converted to mechanical (and probably electrical) energy. Regardless, that doesn't stop us from using the water to power rotational motion where we can.
Comment: @JohnKip Have you ever used a magnifying glass as a toy camera lens to focus an image on a piece of paper/card/wood/wall? I used to do that a lot as a kid. The image generated by camera lenses is upside-down and flipped left to right. That's the natural image of a camera - flipped around/rotated 180 degrees. Using mirrors will not change the original image thus you'd see the flipped image in the viewfinder. The prism is to rotate/flip the image back upright. It is a GUI fix
Comment: @johnkip The focusing screen is _not_ the image sensor! The focusing screen is located above the reflex mirror. It shows the image produced by the lens system like it would be on the sensor. It is this image you look at through the viewfinder.


Can I ask questions about political ideologies and forms of governments?

Question: Are questions about political ideologies and forms of government considered on-topic for Philosophy.SE?
Comment: Yes, absolutely; philosophy of politics is certainly on point here. As always try to keep it as specific and serious as possible and provide as much theoretical context as you can -- for instance, "what is liberalism?" would not be as constructive as, say, "which political philosophers argued for proposition x (and how/why/what are the most significant responses)?"
Comment: @Joseph: What about questions like "What is the difference between X and Y?" where X and Y are something like Liberalism, Libertariansim, Republicanism, .. etc. Also I wanted to ask about the name of ideologies corresponding to certain beliefs and the relation between ideologies and ethics and religion. Are questions like this considered on topic?
Comment: Questions of this nature are on-topic if formulated clearly as questions about philosophy -- I might suggest framing these as asking after the central points of the debate (most significant issues of contention) between two politico-philosophical perspectives.
Answer: If it is philosophical in nature and has a real answer, definitely!
Comment: Generally, as long as you avoid asking questions which will generate lots of speculation, and narrow them down so they are answerable without writing a whole novel, you should be fine. By "Philosophical in nature" I just meant that questions should generally be about finding out the basic truths and principles about the things around us using logic and reason. I.E. it would fall under a topic of philosophy.
Comment: What about the examples I mentioned in my comment above? I am sorry I cannot judge what is "philosophical in nature" about politics because I am an engineer and I do not have the sufficient educational background.
Answer: Questions about politics—with the qualification that it is a philosophical question—are very welcome here.
You shouldn't worry too much about whether your question(s) are philosophical enough. If you're unsure, you can either:

Just try them out by asking them on the site, and we will give feedback one way or the other; or
You can post a question here on Meta explaining your proposed question, and soliciting advice on whether it would be on topic. Even if it's not on topic as you've currently formulated it, I'm sure someone can help you modify the question so that it is well suited for the site.


Should questions marked as too broad have more suggestions on how to improve those questions?

Question: I think it would be a good idea for anyone who marks a question as "too broad" have to give a small comment or explanation behind it. This would lead to better editing and higher quality questions instead of just locking a question out of being answered altogether. It's quite discouraging to have a question marked on hold when I myself think the question would have received good answers. What do you all think?
Comment: I believe this is a good idea, and I wonder even if the reason mustn't be mandatory, as from what I see regularly, "too broad" closure is often used to close questions that are not easy to answer, or require expertise in a domain that is not common. The consequence is that the stack revolves over sempiternal topics and doesn't expand. It was already mentioned earlier that "too broad" is not to be used for "I don't know the answer, and I don't know who could provide the answer".
Comment: You can always edit the question to make it less *broad* and submit to get reopened.
Comment: Suggestions would be helpful to better edit the question.  I feel that some questions I ask are specific enough, but some others feel they aren't. I just feel it would make asking questions less frustrating.
Answer: I disagree that this is necessary. The banner contains all the information and links you require:

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question.
  If this question can be reworded to fit the rules in the help center, please edit the question.

That link to the help center is not the help homepage - it is to a specific section about closed questions where more detail is avilable

too broad - if your question could be answered by an entire book, or has many valid answers (but no way to determine which - if any - are correct), then it is probably too broad for our format

Any comments made when voting to close as too broad would simply duplicate that information in varying and opinionated ways.
Comment: "*Any comments made when voting to close as too broad would simply duplicate that information*". Not necessarily: "I'm voting... too broad because *an accurate answer cannot be provided if you don't specify a country*" etc.
Comment: @mins sure - that's being helpful and I'm not saying you shouldn't do that - I'm just saying its often unnecessary.


Debt to a non muslim

Question: Assalamualaikum, I have a debt with a non-muslim, and the owner have gone missing or hard to reach because he live so far away from me, they are in another country as example. How can I pay my debt back? Should I make a sadakah/donation with their name?
Answer: I can't imagine that in these modern times you neither have an Adress nor Email nor Phone contact of this person nor know anybody who could act as an intermediate to get any of these. Maybe it is even possible to retrieve this person on the internet. A debt is a due and you must try hard to pay it back before coming with "easy" solutions.
Generally this means you must try to find and locate this person to pay him the debt back. If you tried all possible options and failed you must wait a good while (some months a year whatever seems reasonable for expecting a return of the obligee) maybe your obligee comes back and ask his wealth back.
After this time you may do sadaqa on his behalf.
If someday your obligee turns back asking about his wealth there still are two possibilities up to his choice (not yours) accepting the sadaqa or insisting on payback.
Note that a non-Muslim can't get rewards for such a deed according the view of at least some scholars.

Debt to a non muslim


How do I know when to replace/maintain the crank?

Question: What are the warning signs that a crank (not the chainwheel etc, but the crank itself) is worn out and needs to be changed, or removed and cleaned? I have never changed mine in 5 years or so, because it seemed to fall into the category of 'it's working, don't mess with it'. It makes a bit of a grinding sound now and visibly has dirt in it, but still works fine.  Do I wait till it breaks or what?
Comment: A crank -- axle, bearing, cups, and arms -- will last decades and 10s of thousands of miles if the bearings are not somehow damaged and the crank arms are not allowed to loosen.  Your "grinding noise" is worrisome, though -- any bearing that makes noise is not long for this world.
Comment: What kind of bottom bracket do you have?
Answer: There are two cranks or crank arms on a bike - they connect the bottom bracket to the pedals.  Some bikes have a "one piece crank" which combines the functions of the cranks and the bottom bracket axle.
There are four things that go wrong with crank arms
1 The threads for the pedal get stripped/damaged to the point the pedal gets undone easily
2 The mating hole for the bottom bracket fretts and is no longer a good fit.  This often produces a creak on the power part of the stroke.
3 Cracked crank arm - if the mating hole wears, and is retightened enough times, the crank arm slides too far onto the bottom bracket.  With time this can crack the weakest part of the circumference at the BB end of the crank.  This can also happen at the pedal end, but that's unusual.
4 Bends and twists due to impact or accident - this is quite rare because crank arms tend to be very strong, much stronger than frames.
If your problem is the Bottom Bracket, then that's a whole different set of answers.  Grinding could be bearings (check for play in the bottom bracket axle) or it could be a bad chainline, so the chain may be dragging on the front mech cage and your shifter wires need a tweak.
Answer: take out the chain and rotate the crankset as fast as you can, there shouldn't be any sound like creaking ir grinding. then check for any play. i generaly take out and clean mine every year. if you have shimano bottom bracket just outside clean and replace if something wrong with it. if it's sram gxp bottom bracket you should deep clean and grease it.


Joining line segments to make tree

Question: Given a set of disjoint line segments in the plane, prove (or disprove) that we can always join the line segments to make a tree where the vertices of the tree are the endpoints of the segments and every segment is an edge in the tree.
Answer: Disclaimer: the proof is quite technical. OTOH, I don't see a comfortable way to do this, because the initial set of segments can be as crazy as possible, even if none of them intersects.
Let's prove that we can make a tree not only from the set of disjoint segments, but also from the set of disjoint trees. So, the initial statement will be just a special case of it when all trees are segments.
The new statement will be proved by downward induction on the number of trees. When we have only one tree, we are done. To make an induction step, it's enough to connect two trees without intersecting or touching other trees.
Define distance between different trees $S$ and $T$ as $d(S, T) = min_{s\in P(S), t\in P(T)}d(s, t)$, where $P(X)$ is a set of all points belonging to tree $X$ (not necessarily vertices), $d(s, t)$ is a usual Euclidean distance.
Then take $(S, T) = argmin_{R, W \hbox{ are trees}, R \ne W} d(R, W)$. Let $d_0 = d(S,T)$. Also define $s$ and $t$ as the points which deliver us the minimum distance.
WLOG $s$ is a vertex. This statement requires some geometrical analysis. The most complicated case is when $s$ and $t$ lie strictly inside some segments. But if so, these segments must be parallel to each other, otherwise we can draw a height from some point to the opposite segment and get a distance smaller than $d_0$. And if they are parallel, the segment $st$ is perpendicular to them both, and we can simply move it to the one of the ends of the segments, so one of points actually becomes a vertex.
First, prove that the segment $st$ doesn't intersect or touch other existing segments. We do it by contradiction. If such segment exists, set the intersection point to $u$. It lies strictly inside $st$, because the tree set is disjoint and not self-intersecting. There is a tree $U$ such that $u\in U$. But either $U \ne T$ or $U \ne S$, thus $d(U, T)$ or $d(U, S)$ is well-defined and is smaller than $d(s, t) = d_0$. Contradiction.
Second, if $t$ is already a vertex, we are done, because we can draw a new segment connecting vertices $s$ and $t$. Otherwise define the segment which $t$ belongs to as $K$.
Third, let's continuously move $t$ on $K$ to one of the ends of $K$. If we reach the end without $st$ touching any other points, we are done. If not, assume that we got a segment $st'$ for $t'\in T$, and also $st'$ contains some other vertex $v \in V$. If there are more than one such vertex, take closest to $s$.
Let's look what happens if $V \ne T$. Geometry says that $st$ is perpendicular to $K$. So, if we draw a height from $v$ to $K$, we get a segment shorter than $st$, and it will deliver a distance from $V$ to $T$ smaller than $d_0$.
And if $V = T$, we can just forget about $t$ and connect $S$ and $T$ using segment $sv$.
Answer: I'd like to propose a variation on Aleksandr Logunov's proof, that I find to be a bit simpler (arguable).
Let's prove that we can make a tree from a collection of disjoint trees.
So suppose we have a collection of at least two disjoint trees in the plane (if there were only one we would be done).
Without loss of generality, suppose that no two vertices have the same $x$ coordinate (otherwise, just rotate the plane ever so slightly to make this hold).
Choose a vertex $u$ which is the rightmost vertex of some tree but not the overall rightmost vertex (such a vertex necessarily exists if we have at least two trees and no two vertices have the same $x$ coordinate).
Choose a vertex $v$ to the right of $u$. Draw the segment $(u,v]$ and let $S$ be the first segment $(u,v]$ intersects, and $p$ the point of this intersection.
If $p = v$, then we can safely draw the segment $[u,v]$ and decrease the number of connected components in our forest (remember that $v$ is not in the same tree as $u$ because $u$ is the rightmost vertex of its tree).
If $p \neq v$, then let $w$ be a vertex of $S$ to the right of $u$ ($S$ has at least one such vertex). Just like in Aleksandr's proof, we can now move $p$ on $S$ towards $w$ until the segment $(u,p]$ intersects a vertex. We can then safely draw the segment joining $u$ to that vertex and decrease the number of connected components by one.
So we can always decrease the number of connected components by one (if we have at least two to start with) and thus the result follows by induction.

Joining line segments to make tree


Remote desktop to a computer that's asleep

Question: Is it possible to remote into my home desktop when it's asleep?  Is it possible to remotely wake it up?
Answer: Wake-on-LAN will be the key.
Lifehacker covered it well here: http://blog.lifehacker.com/#!348197/access-your-computer-anytime-and-save-energy-with-wake+on+lan
Read this thread too if you need more details.
gl, mjb.
Answer: Yes, you want wake-on-lan. Many VNC client software include it, but it's a minor thing easy to find elsewhere (oddly ios vnc clients seem to be more likely to have it, also where there are really nice wol apps).
Here's an explanation for windows, it's even easier on mac (look in Energy Saver).
Answer: Go to your bios and enable the 'wake on lan' option (if you have the option , other wise there is not much you can do ),
Also you might need a 'wake on lan' tool to wake it up .


Were there any dementors in Nurmengard?

Question: Were there any dementors in Nurmengard at all? If there weren't, it seems ironic that one of the most darkest wizards, Grindelwald, was being kept in a relatively less-punishing place, unlike Azkaban where all prisoners, irrespective of the severity of the crime, are exposed to the horror of the dementors.
Answer: No.
There were no Dementors in Nurmengard.
It should be noted that the Dementors only resided in Azkaban because it was a natural breeding ground, even before the site became used as a prison.

Those who entered to investigate refused afterwards to talk of what they had found inside, but the least frightening part of it was that the place was infested with Dementors...The very walls of the building seemed steeped in misery and pain, and the Dementors were determined to cling to it. Experts who had studied buildings built with and around Dark magic contended that Azkaban might wreak its own revenge upon anybody attempting to destroy it. The fortress was therefore left abandoned for many years, a home to continually breeding Dementors.
(Pottermore, "Azkaban").

So we wouldn't expect Dementors in Nurmengard anyway.
The details we have on Nurmengard are few and far between. Whether its design appears effective to us or not, it obviously was effective as it contained one of the most feared dark wizards for over 50 years. If your most dangerous prisoner dies inside the walls then your prison design must be sound!
How did it contain its prisoners? We only get snippets of description from the books but what we do get is suggestive.

...he was gliding around the high walls of the black fortress -
  [...]
  ...looking up, up to the topmost window, the highest tower -
  [...]
  ...time to fly -
  [...]
  ...and he rose into the night, flying straight up to the window at the very top of the tower -
  [...]
  ...the window was the merest slit in the black rock, not big enough for a man to enter...a skeletal figure was just visible through it, curled beneath a blanket...dead or sleeping...?
  [...]
  ...as he forced himself through the slit of a window like a snake and landed, lightly as vapour, inside the cell-like room -
(Deathly Hallows, Chapter 23, Malfoy Manor).

From this we can deduce that Nurmengard is a tall, black tower which keeps its most dangerous prisoners at the top. It does have windows but these are mere slits.
The most powerful defence that Nurmengard has going is shared by Azkaban: it denies its prisoners their wands. Whilst some rudimentary magic is possible without a wand this really is extremely limited. Voldemort got through the window, but only with a wand. Grindelwald never managed to, probably because he couldn't manage that feat without a wand. Even if he were to somehow blast a hole in the wall or slide through using magic he faced a huge drop. This could be survived by using a Cushioning Charm (as demonstrated by Hermione in Gringotts), but not without the use of a wand. Like Azkaban, Nurmengard relies on its geography. Without a wand, Grindelwald would have been in for a nasty fall.
Presumably there were measures in place which prevented outside interference to break prisoners out. There were probably guards around, although they're never mentioned and Voldemort doesn't come across them. Otherwise, Grindelwald's followers would probably have flown in on broomsticks and set him free.
Comment: Neville has survived being dropped out the window without a wand — why wouldn't a prisoner survive fall from the top of the tower?
Comment: @Ruslan Why? Well, why, of course - magic! [Cats and infants do that all the time!](http://www.bbc.co.uk/news/magazine-17492802)
Comment: @Ruslan Good question. Neville was dropped accidentally and was responding on instinct. I'm not sure that he would've tried repeating the trick. There might also be a difference between a first-floor window and a cell at the top of a huge tower. You're right, it's not fully explicable. But all I'd say is that Neville survived through impulsive magic (and almost drowned on an earlier occasion when thrown off Blackpool pier), which doesn't guarantee survival and so isn't the sort of magic you would depend on when planning an escape.
Comment: @Ruslan It was a smaller fall, and it's not clear exactly what spell he used to do so, so it's not clear whether the same thing would work on a larger fall or not. It is worth noting, though, that it's evidently possible to at least reduce the effects of falls without a wand. In the movie version  of the third book at least, Dumbledore wandlessly cast "arresto momentum" to slow Harry's fall after he fell off his broom from a significant height due to the Dementors. (Harry was still knocked out and had to go to the hospital wing to recover, though, so it wouldn't have helped escape).
Comment: Harry was knocked out already from the Dementors. The fall didn't do it... He wouldn't have fallen to begin with if the Dementors didn't make him pass out. So if Grindelwald could perform the same thing on himself, it may work. The issue is blowing out the wall, which could be reinforced by magic anyway, so a wandless, weak spell would just fizzle out anyway. Who fully knows, though...

Were there any dementors in Nurmengard?


Exp:resso Store tax exempt customers?

Question: Is there a way in Exp:resso Store to allow certain customers to be marked tax-exempt and then omit tax based on their status? Ideally a customer would contact us with their tax-exempt number and we would mark them tax-exempt in their member account. Or a member could include their tax-exempt number in a custom field when registering? Once that is filled in for their account, though, how could I omit tax for their orders?
Answer: There is nothing out of the box that I know that would allow you to do this. Your best bet would be to create an extension that uses the store_order_taxes hook to see if the member has a certain field of their profile populated.
Having said that you would probably need to either have only an admin be able to fill out that field or have some logic to make sure that the tax-exempt number is valid so that the end user doesn't just enter a random number.

Exp:resso Store tax exempt customers?


Enable dragging on leaflet map for popup div within map

Question: I'm sorry for my English, I just study it.
Is it possible to save map-draggable functionality on popup within leaflet map? I mean move the map while dragging(clicking and moving or tuching on mobile) across the popup?
Comment: Save where: on users computer, on server?
Comment: No, I meant to keep the functionality of moving the map when clicking/dragging on the popup. By default, the map does not move when you click/drag on the popup area, it moves only when you click/drag on the map itself.
Answer: You can enable dragging the whole map when mouse is pressed on popup by making popup content ignore the mouse events.
This can be achieved by modifying appropriate Leaflet CSS styles:
<code>.leaflet-popup-content-wrapper {
   pointer-events: none;
}
.leaflet-popup-tip-container {
   pointer-events: none;
}
</code>
Comment: Thank you a lot! It works well. But what if popup has a button? Button will not be working too. I need this behavior only on mobiles. Can this be done with JS and events? I try until it works.
Comment: Popup close button will be working, it's in a separate `div` element with `leaflet-popup-close-button` CSS class.
Comment: I have another button on popup and big clickable image. I add CSS property to them "pointer-events: auto" and it works... But not so pretty. Is it possible for the entire area of popup (with button and clickable image) to be with draggable map, but click events work?
Comment: It would probably be possible, but with a lot of event processing.


Is there a PPA with the latest version of LibreOffice?

Question: There was recently another release of LibreOffice, but it is  a pain to have to manually go to their website and download the packages every time there is a new release. Is there a PPA that always has the latest version of LibreOffice?
Comment: Those who have already installed libreoffice-4.0 with the above mentioned ppa they will have to just run this command in the terminal $ sudo apt-get dist-upgrade THIS WILL UPGRADE YOUR LIBREOFFICE 4.0 TO 4.1
Answer: There is an official LibreOffice PPA here.
You need to add ppa:libreoffice/ppa in your software sources to add it to the software center, just follow the instructions for the GUI way.
More information:

Is the ppa of LibreOffice to be considered safe for the system?

To add ppa and upgrade libre office using command line:
sudo add-apt-repository ppa:libreoffice/ppa
sudo apt-get update
sudo apt-get upgrade

Comment: This worked for me, although I did have to check for further upgrades to other packages that were "held back" after this. Running apt install  fixed the issue.
Answer: UPDATE 2
As of July 25th 2013, the following PPA offers the Release version of LibreOffice:
sudo add-apt-repository ppa:libreoffice/ppa
sudo apt-get update
sudo apt-get upgrade

That will leave you with LibreOffice 4.1.

UPDATE 1
A PPA is now available for 4.1.0.  To add it, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:
sudo add-apt-repository ppa:libreoffice/libreoffice-prereleases

For complete instructions on how to install the beta2 of Libreoffice 4.1.0, check out LibreOffice Pre-Releases

ORIGINAL ANSWER
I have searched high and low, and I can't find a PPA for 4.1.x.  Now if you would like to install it, (the documentation doesn't mention removing prior installation) I would recommend that you remove previous versions before installing this one.
To install LibreOffice 4.1.0 Beta 1 on Ubuntu 13.04, 12.10, and 12.04, do this.  Just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:
For 32 bit systems:
wget -c dev-builds.libreoffice.org/pre-releases/deb/x86/LibreOfficeDev_22.214.171.124.beta1_Linux_x86_deb.tar.gz

For 64 bit systems:
wget -c dev-builds.libreoffice.org/pre-releases/deb/x86_64/LibreOfficeDev_18.104.22.168.beta1_Linux_x86-64_deb.tar.gz

Extract the archive:
eDev_4.1.0.tar -zxvf LibreOffic0.beta1_Linux_x86*_deb.tar.gz

Install LibreOffice 4.1.0:
cd LibreOfficeDev*/DEBS
sudo dpkg -i *

As of June 13, 2013 it still not available in the pre-release PPA.  Once available will update the answer.
Source:LinuxG
Comment: It's time to upkeep this great answer and sort the updates made to it by decresing time order. I mean: Put first "As of july 25 ...".
Comment: i had to do a `sudo apt-get dist-upgrade` instead of just `update`.
See this [Server fault answer](http://serverfault.com/questions/46748/can-someone-clarify-ubuntu-debian-dist-upgrade-for-me/46749#46749) for better explanation of `dist-upgrade`
Answer: The main LibreOffice PPA is for "test builds and backports", including "alpha and beta releases!".
UPDATE As of 2016-07, I see it's "LibreOffice fresh", the latest release of the newest series (but no alpha/beta releases, which are now in separate PPA).
If you want less-bleeding edge, it includes links to per-version stable PPAs, e.g. https://launchpad.net/~libreoffice/+archive/libreoffice-4-1 for LibreOffice 4.1.
Answer: If you wish to use a Pre-Release (Alpha, Beta or Pre-Release version) you can use the following PPA:
sudo add-apt-repository ppa:libreoffice/libreoffice-prereleases
sudo apt-get update
sudo apt-get upgrade

This will give you the latest Pre-Release version available. It works perfectly with LibreOffice 4.2.x (At this moment). If you get any problems related to broken packages or the likes you can force the upgrade procedure which fixes any related problems with the already installed packages. In the case however I would recommend using aptitude instead of apt-get (For a better dependency resolver) like this:
sudo aptitude full-upgrade

Of course this is only in the worst case scenario but always remember to read the recommendations of aptitude before proceeding which mentions which packages will be removed, upgraded and installed.


Web app for learning American Sign Language

Question: What web application is most suitable for learning the common non-English visual language used by the educated U.S. Deaf community?
Comment: This seems to be a resource request (similar to asking for a book etc.), so I think it's off-topic here.
Answer: As a native sign language user I highly suggest you start with lifeprint.com it is excellent for the free YouTube videos and the dictionary explains the many nuances and uses of each word. It helps a lot to see the signer from two angles, and having a newish signer in the videos helps people following the videos learn about and avoid the most common mistakes.
There is also signingsavvy.com which is subscription based, helpful for people without English background or visual learners since there are images associated with each word. It has an app as well, but no images on the app version unfortunately.
Once you've learned enough, you can start watching videos posted to the ASLThat FB page (no subtitles or voice audio, you need to know the basics of ASL to follow it) and there's also several great communities on Reddit: r/asl & you can get someone to practice with online at either r/deafskype or r/aslpenpal.
howyousign.com is a great launchpad to get you started on discovering different resources available for learning ASL or the interpreting profession.
Last but not least, seek out Deaf Night Out events in your location and try to get a real life deaf buddy who's willing to mentor you. DNO tends to happen on Friday nights at either a cafe or a pub. It's the best way to learn. Books (even current ones) will teach outdated signs, or rather signs that are not used regionally. Sign language varies a lot, by country, and even within a country there are many accents or dialects just like spoken languages. For example, there are more than 21 different signs for the word Strawberry.


Mastercard in Japan - pay with signature

Question: I'm in Japan and I have a Mastercard, but I forgot my PIN. Do you know if it is possible to swipe and pay?
Comment: Before, we could go to any bank and withdrawal directly, the bank will call and authorize and then give you cash. Not sure if this is applicable now or not.
Comment: Some banks will let you change your PIN via their website or over the phone.
Comment: If you ran out of options, and you are from the US, then you can transfer money from your credit card to MoneyGram anywhere in the world using PayPal, you will not need the pin to use the credit card online and you will be able to add money to your PayPal account then transfer it to yourself via moneygram and collect it instantly, check this page: https://paypal.moneygram.com/home.html
Comment: For us there was a 1% charge to use the Postal ATM machine when transferring money to Japan. Compared to any other option that was cheap.
Answer: Japan is a bit behind the curve for chip & PIN, it's now possible in some places but swipe & sign remains universally accepted.  Do remember that Japan remains a cash-heavy society and there are lots of smaller shops, restaurants and accommodations that operate on a cash-only basis.
The only time you really need a PIN is for cash advances from ATMs, although most Japanese ATMs don't accept any foreign credit cards period (see Wikivoyage for the gruesome, ever-changing details).
Comment: @Aditya, in my decade plus in Japan, I have never seen an additional charge for using a credit card. The only time I have seen a difference in price is when at an electronics store you can occasionally get a 3-5% discount for paying with cash. Recently at least in urban areas, just about everywhere that I would expect to accept credit cards does (the only cash-only businesses I can think of in major urban areas are smaller bars and restaurants).
Comment: As answered above, swipe & sign is basically OK everywhere that accepts credit cards.  However, you will not be able to use it at machines that sell JR tickets (like bullet train tickets).  If you go to the counters with people selling JR tickets (usually next to the machines) you can swipe the credit card and use it, so if you want a bullet train ticket definitely line up at the counter (with people) selling them, not the machines.
Comment: As jpatokal mentioned it is primarily a cash based society so expect additional fee *everywhere* if you wish to use your credit card. Obviously at popular spots such as JR stations, I doubt extra fee is applicable, but I'd rather try and call my bank and get my PIN changed.
Comment: @jmac That's odd. I saw extra money for credit card a week back, at Kappabashi-dori. Other times, I've been to places where it's just more hassle. Popular restaurants and shopping malls usually work fine.
Comment: @Aditya, for places offering the cheapest price possible (including discount sites like kakaku.com), credit cards are often not accepted to keep the prices down. In many countries, the credit card companies lobbied to make sure there can't be a cheaper 'cash only' price to reduce barriers to people using cards more (I do not know if that's the case in Japan). In many shops you can haggle a lower price if paying by cash (if not offered a discount automatically), but I would hesitate to say *"expect additional fee everywhere if you wish to use your credit card"*
Comment: @jmac That would be correct indeed. In some places yeah. Not everywhere. My bad. :D


How to draw text using only OpenGL methods?

Question: I don't have the option to use but OpenGL methods (that is glxxx() methods). I need to draw text using gl methods only. After reading the red book, I understand that it is possible only through the glBitmap() method. If this is the only possible way, then can any one help me with the pixel array information for all the characters. Is there is any other way to draw text?
Answer: Theory
Why it is hard
Popular font formats like TrueType and OpenType are vector outline formats: they use Bezier curves to define the boundary of the letter.

Image source.
Transforming those formats into arrays of pixels (rasterization) is too specific and out of OpenGL's scope, specially because OpenGl does not have non-straight primitives (e.g. see Why is there no circle or ellipse primitive in OpenGL?)
The easiest approach is to first raster fonts ourselves on the CPU, and then give the array of pixels to OpenGL as a texture.
OpenGL then knows how to deal with arrays of pixels through textures very well.
Texture atlas
We could raster characters for every frame and re-create the textures, but that is not very efficient, specially if characters have a fixed size.
The more efficient approach is to raster all characters you plan on using and cram them on a single texture.
And then transfer that to the GPU once, and use it texture with custom uv coordinates to choose the right character.
This approach is called a texture atlas and it can be used not only for textures but also other repeatedly used textures, like tiles in a 2D game or web UI icons.
The Wikipedia picture of the full texture, which is itself taken from freetype-gl, illustrates this well:

I suspect that optimizing character placement to the smallest texture problem is an NP-hard problem, see: What algorithm can be used for packing rectangles of different sizes into the smallest rectangle possible in a fairly optimal way?
The same technique is used in web development to transmit several small images (like icons) at once, but there it is called "CSS Sprites": https://css-tricks.com/css-sprites/ and are used to hide the latency of the network instead of that of the CPU / GPU communication.
Non-CPU raster methods
There also exist methods which don't use the CPU raster to textures.
CPU rastering is simple because it uses the GPU as little as possible, but we also start thinking if it would be possible to use the GPU efficiency further.
This FOSDEM 2014 video explains other existing techniques:

tesselation: convert the font to tiny triangles. The GPU is then really good at drawing triangles. Downsides:

generates a bunch of triangles
O(n log n) CPU calculation of the triangles

calculate curves on shaders. A 2005 paper by Blinn-Loop put this method on the map. Downside: complex. See: Resolution independent cubic bezier drawing on GPU (Blinn/Loop)
direct hardware implementations like OpenVG. Downside: not very widely implemented for some reason. See:

OpenGL, OpenVG. Draw text?
OpenVG implementation?

Fonts inside of the 3D geometry with perspective
Rendering fonts inside of the 3D geometry with perspective (compared to an orthogonal HUD) is much more complicated, because perspective could make one part of the character much closer to the screen and larger than the other, making an uniform CPU discretization (e.g. raster, tesselation) look bad on the close part. This is actually an active research topic:

What is state-of-the-art for text rendering in OpenGL as of version 4.1?

Valve's 20017 signed distance field paper. Previously at: http://www.valvesoftware.com/publications/2007/SIGGRAPH2007_AlphaTestedMagnification.pdf But companies can't not break URLs eventually.
https://www.youtube.com/watch?v=1b5hIMqz_wM by
Martin Donald (2020) is a nice video commenting on it, and it seems to give some more concrete usage advice as well.

Distance fields are one of the popular techniques now.
Implementations
The examples that follow were all tested on Ubuntu 15.10.
Because this is a complex problem as discussed previously, most examples are large, and would blow up the 30k char limit of this answer, so just clone the respective Git repositories to compile.
They are all fully open source however, so you can just RTFS.
FreeType solutions
FreeType looks like the dominant open source font rasterization library, so it would allow us to use TrueType and OpenType fonts, making it the most elegant solution.

https://github.com/rougier/freetype-gl
Was a set of examples  OpenGL and freetype, but is more or less evolving into a library that does it and exposes a decent API.
In any case, it should already be possible to integrate it on your project by copy pasting some source code.
It provides both texture atlas and distance field techniques out of the box.
Demos under: https://github.com/rougier/freetype-gl/tree/master/demos
Does not have a Debian package, and it a pain to compile on Ubuntu 15.10: https://github.com/rougier/freetype-gl/issues/82#issuecomment-216025527 (packaging issues, some upstream), but it got better as of 16.10.
Does not have a nice installation method: https://github.com/rougier/freetype-gl/issues/115
Generates beautiful outputs like this demo:

libdgx https://github.com/libgdx/libgdx/tree/1.9.2/extensions/gdx-freetype

Examples / tutorials:

a NEHE tutorial: http://nehe.gamedev.net/tutorial/freetype_fonts_in_opengl/24001/
http://learnopengl.com/#!In-Practice/Text-Rendering mentions it, but I could not find runnable source code
SO questions:

OpenGL font rendering using Freetype2
Text not rendering correctly - OpenGL using FreeType2

Other font rasterizers
Those seem less good than FreeType, but may be more lightweight:

https://github.com/nothings/stb/blob/master/stb_truetype.h
http://www.angelcode.com/products/bmfont/

Anton's OpenGL 4 Tutorials example 26 "Bitmap fonts"

tutorial: http://antongerdelan.net/opengl/
source: https://github.com/capnramses/antons_opengl_tutorials_book/blob/9a117a649ae4d21d68d2b75af5232021f5957aac/26_bitmap_fonts/main.cpp

The font was created by the author manually and stored in a single .png file. Letters are stored in an array form inside the image.
This method is of course not very general, and you would have difficulties with internationalization.
Build with:
make -f Makefile.linux64

Output preview:

opengl-tutorial chapter 11 "2D fonts"

tutorial: http://www.opengl-tutorial.org/intermediate-tutorials/tutorial-11-2d-text/
source: https://github.com/opengl-tutorials/ogl/blob/71cad106cefef671907ba7791b28b19fa2cc034d/tutorial11_2d_fonts/tutorial11.cpp

Textures are generated from DDS files.
The tutorial explains how the DDS files were created, using CBFG and Paint.Net.
Output preview:

For some reason Suzanne is missing for me, but the time counter works fine: https://github.com/opengl-tutorials/ogl/issues/15
FreeGLUT
GLUT has glutStrokeCharacter and FreeGLUT is open source...
https://github.com/dcnieho/FreeGLUT/blob/FG_3_0_0/src/fg_font.c#L255
OpenGLText
https://github.com/tlorach/OpenGLText
TrueType raster. By NVIDIA employee. Aims for reusability. Haven't tried it yet.
ARM Mali GLES SDK Sample
http://malideveloper.arm.com/resources/sample-code/simple-text-rendering/ seems to encode all characters on a PNG, and cut them from there.
glText
https://github.com/vallentin/glText
Single header C library, that uses a bitmap font baked into the library.

SDL_ttf

Source: https://github.com/cirosantilli/cpp-cheat/blob/d36527fe4977bb9ef4b885b1ec92bd0cd3444a98/sdl/ttf.c
Lives in a separate tree to SDL, and integrates easily.
Does not provide a texture atlas implementation however, so performance will be limited: How to render fonts and text with SDL2 efficiently?
Related threads

How to do OpenGL live text-rendering for a GUI?
Text/font rendering in OpenGLES 2 (iOS - CoreText?) - options and best practice?
Answer: Drawing text in plain OpenGL isn't a straigth-forward task. You should probably have a look at libraries for doing this (either by using a library or as an example implementation).
Some good starting points could be GLFont, OpenGL Font Survey and NeHe Tutorial for Bitmap Fonts (Windows).
Note that bitmaps are not the only way of achieving text in OpenGL as mentioned in the font survey.
Answer: This article describes how to render text in OpenGL using various techniques.
With only using opengl, there are several ways:

using glBitmap
using textures
using display lists
Answer:
Use glutStrokeCharacter(GLUT_STROKE_ROMAN, myCharString).
An example: A STAR WARS SCROLLER.
#include <windows.h>
#include <string.h>
#include <GL\glut.h>
#include <iostream.h>
#include <fstream.h>

GLfloat UpwardsScrollVelocity = -10.0;
float view=20.0;

char quote[6][80];
int numberOfQuotes=0,i;

//*********************************************
//*  glutIdleFunc(timeTick);                  *
//*********************************************

void timeTick(void)
{
    if (UpwardsScrollVelocity< -600)
        view-=0.000011;
    if(view < 0) {view=20; UpwardsScrollVelocity = -10.0;}
    //  exit(0);
    UpwardsScrollVelocity -= 0.015;
  glutPostRedisplay();

}

//*********************************************
//* printToConsoleWindow()                *
//*********************************************

void printToConsoleWindow()
{
    int l,lenghOfQuote, i;

    for(  l=0;l<numberOfQuotes;l++)
    {
        lenghOfQuote = (int)strlen(quote[l]);

        for (i = 0; i < lenghOfQuote; i++)
        {
          //cout<<quote[l][i];
        }
          //out<<endl;
    }

}

//*********************************************
//* RenderToDisplay()                       *
//*********************************************

void RenderToDisplay()
{
    int l,lenghOfQuote, i;

    glTranslatef(0.0, -100, UpwardsScrollVelocity);
    glRotatef(-20, 1.0, 0.0, 0.0);
    glScalef(0.1, 0.1, 0.1);

    for(  l=0;l<numberOfQuotes;l++)
    {
        lenghOfQuote = (int)strlen(quote[l]);
        glPushMatrix();
        glTranslatef(-(lenghOfQuote*37), -(l*200), 0.0);
        for (i = 0; i < lenghOfQuote; i++)
        {
            glColor3f((UpwardsScrollVelocity/10)+300+(l*10),(UpwardsScrollVelocity/10)+300+(l*10),0.0);
            glutStrokeCharacter(GLUT_STROKE_ROMAN, quote[l][i]);
        }
        glPopMatrix();
    }

}
//*********************************************
//* glutDisplayFunc(myDisplayFunction);       *
//*********************************************

void myDisplayFunction(void)
{
  glClear(GL_COLOR_BUFFER_BIT);
  glLoadIdentity();
  gluLookAt(0.0, 30.0, 100.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
  RenderToDisplay();
  glutSwapBuffers();
}
//*********************************************
//* glutReshapeFunc(reshape);               *
//*********************************************

void reshape(int w, int h)
{
  glViewport(0, 0, w, h);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluPerspective(60, 1.0, 1.0, 3200);
  glMatrixMode(GL_MODELVIEW);
}

//*********************************************
//* int main()                                *
//*********************************************

int main()
{
    strcpy(quote[0],"Luke, I am your father!.");
    strcpy(quote[1],"Obi-Wan has taught you well. ");
    strcpy(quote[2],"The force is strong with this one. ");
    strcpy(quote[3],"Alert all commands. Calculate every possible destination along their last known trajectory. ");
    strcpy(quote[4],"The force is with you, young Skywalker, but you are not a Jedi yet.");
    numberOfQuotes=5;

    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
    glutInitWindowSize(800, 400);
    glutCreateWindow("StarWars scroller");
    glClearColor(0.0, 0.0, 0.0, 1.0);
    glLineWidth(3);

    glutDisplayFunc(myDisplayFunction);
    glutReshapeFunc(reshape);
    glutIdleFunc(timeTick);
    glutMainLoop();

    return 0;
}

Comment: glutStrokeCharacter is not a opengl function
Comment: it fits in glxxx() OP requirement though :)
Comment: Here's the code modified to work on Ubuntu (glutInit, includes): https://gist.github.com/tgandor/3963f112324030a2c833
Comment: You have a buffer overflow in your fourth quote !
Comment: Seems you are correct. "Alert all commands. Calculate every possible destination along their last known trajectory. " is a 92-byte string, but only 80 bytes have been allocated.
Answer: Load an image with characters as texture and draw the part of that texture depending on what character you want. You can create that texture using a paint program, hardcode it or use a window component to draw to an image and retrieve that image for an exact copy of system fonts.
No need to use Glut or any other extension, just basic OpenGL operability. It gets the job done, not to mention that its been done like this for decades by professional programmers in very succesfull games and other applications.
Comment: There are even programs that you can use to generate the image texture for you.
Answer: I think that the best solution for drawing text in OpenGL is texture fonts, I work with them for a long time. They are flexible, fast and nice looking (with some rear exceptions). I use special program for converting font files (.ttf for example) to texture, which is saved to file of some internal "font" format (I've developed format and program based on http://content.gpwiki.org/index.php/OpenGL:Tutorials:Font_System though my version went rather far from the original supporting Unicode and so on). When starting the main app, fonts are loaded from this "internal" format. Look link above for more information.
With such approach the main app doesn't use any special libraries like FreeType, which is undesirable for me also. Text is being drawn using standard OpenGL functions.
Comment: If I may add something to this already good answer, pay attention to the optmization of any font rendering system since it may impact the performances of your engine on very limited HW resources such as mobile devices.


What is the Greek etymology for "-on" in words like "proton" and "neutron"?

Question: Google says "proton" is from "protos" and "-on" ("first" + "being"), or "πρῶτος" and "?". What is the "-on" in Greek, is it "ὤν" or "ἐν" or something?
Comment: But this is an English site, not a Greek site …
Comment: Folks, this is an English etymology question alright.
Comment: Ancient Greek is normally treated at https://latin.stackexchange.com or the etymology can also be asked at https://linguistics.stackexchange.com
Comment: As John Lawler observes in a comment beneath the accepted answer, the '-on' suffix in electron (and in argon) is '-ον' (omicron nu).
Answer: -on, from ion, Greek present participle of ienai (go)
Electron:

coined 1891 by Irish physicist George J. Stoney (1826-1911) from electric + -on, as in ion.

ion (n.):

1834, introduced by English physicist and chemist Michael Faraday (suggested by the Rev. William Whewell, English polymath), coined from Greek ion, neuter present participle of ienai "go," from PIE root *ei- "to go." So called because ions move toward the electrode of opposite charge.

(Etymonline)
Comment: @LancePollard If it's super-important that the answer uses Greek script, this really doesn't look like a question about English.
Comment: No, it's omicron nu. The Greek -on singular neuter is cognate to the Latin -um singular neuter; the plural neuter for both languages is -a (alpha in Gk).
Comment: And here I thought electron was already the Greek word for amber
Comment: @user067531 Sorry, which is it? present or past? Your second quote conflicts with your own wording at the top of the answer.
Comment: Can you please write it in greek script, that's the main thing I am looking for.
Comment: @LancePollard - see here https://en.m.wiktionary.org/wiki/%E1%BC%B0%CE%AD%CE%BD%CE%B1%CE%B9
Comment: How about for the `on` part specifically, is it omega v or what?
Comment: The Greek words are [ἰόν](https://en.wiktionary.org/wiki/%E1%BC%B0%CF%8C%CE%BD) the neuter present participle of [ἰέναι](https://en.wiktionary.org/wiki/ἰέναι) *(to go)* and [εἶμι](https://en.wiktionary.org/wiki/%CE%B5%E1%BC%B6%CE%BC%CE%B9) *(I go)*
Comment: So is "on" taken to mean "gone", since that is the past participle of "go"?
Comment: @TylerH - "coined from Greek ion, neuter *present participle* of ienai "
Comment: This is false.  πρῶτον
and other words ending in -ον
have, generally, "nothing" to do with ἴον.
Answer: Here's the Oxford English Dictionary's etymology for the ending -on:

-on (in electron n.2, itself after earlier ion n.), reinforced in both senses by -ον as a termination of Greek neuter nouns and adjectives and their derivatives, and (especially in sense 2) perhaps by ancient Greek ὄν being (compare -ont comb. form).

Context:

"Sense 2" is in words like chronon, virion, and codon which are "entities conceived of as discrete or basic units".
-ont is used in words like planont.
Answer: Michael Quinion, Ologies and Isms: Word Beginnings and Endings (Oxford, 2002) breaks its coverage the suffix -on into two entries, starting with this one:

-on1 Subatomic particles or quanta; molecular units. {Originally from electron, probably from the ending of ion and influenced by Greek on, being.}
An electron a a stable subatomic particle with a negative charge. On its model, -on has become the dominant ending with which to label elementary particles and groups of such particles (for another see -tron); ...

Quinion then lists English examples of this line of derivation from the subcategories of particles (proton, meson, baryon), quanta (photon, graviton, phonon), and molecular biology (codon, intron, operon). But that doesn't exhaust the universe of Greek-derived English words ending in -on. Quinion follows with this entry:

-on2 Inert gases. {The Greek neuter ending -on.}
Argon was the first of the inert gases to be discovered; its name was taken from Greek, the neuter of argos, idle, from a- without, plus ergon, work. Others were named in imitation: neon (Greek, literally 'something new', neuter of the adjective neos), krypton (Greek krupton, neuter of kruptos, hidden); xenon (Greek, neuter of xenos, stranger); radon (from radium).

Merriam-Webster's Eleventh Collegiate Dictionary (2003) gives first-occurrence dates of 1891 for electron and 1894 (argon), 1898 (neon, krypton, and xenon), and 1918 (radon) for the inert gases. The odd gas out here is helium, which was named in 1872 and somehow avoided being retroactively renamed helion. As for ion, the possible inspiration for electron, it dates to 1834.
Whether the inert gas names starting in 1894 were influenced by the slightly earlier emergence of electron (in 1891) is a matter of conjecture, but as Quinion shows, the term a-ergon has solid etymological legitimacy in its own right—and the particulate sense of the ion/electron family of words is unmatched by the gases except under a very powerful microscope.
Answer: -ον is the ending of most neütral adjectives (in the singular
nominative).  πρῶτος is masculine, πρῶτον is neütral.
The neütral present participle ὄν (being) of
εἶναι (to be) is
also
an adjective ending in -ον,
but plays no rôle in explaining the form
πρῶτον.
Similarly with
ἴον (going), in spite of the accepted answer.


Why is there such disparity of max contribution limits between 401K accounts and regular IRA accounts?

Question: In 2011, regular IRA accounts allowed only $5,000 maximum contribution, while 401K accounts allowed up to $16,500. Why is there such a disparity? Why do tax advantages favor employees of large employers that can afford 401K programs?
Comment: You're asking the wrong question here. If instead you ask "Why should there be any similarity in limits between two different programs put in place by different Congresses for different reasons at different times?", you'll struggle to get any answers, which should then answer the question you asked.
Comment: Boulding's Backward Basis: "Things are the way they are because they got that way." - Gerald Weinberg
Comment: because those who don't work for an employer with benefits will die anyway because they don't have a decent health insurance, so who cares about them peasants... [me being sarcastic, would love to know the real reason why though]
Comment: These accounts were authorized by congress, they, not the IRS makes these convoluted rules. Their histories are separate but the rules for one interact with the other. It is what it is due to its history. I don't know if you'll find a decent answer comparing the two types of accounts.
Comment: @ChrisW.Rea This thread is on the first page of results for "Boulding's Backward Basis"
Answer: The 401k was not written with the specific intent of enabling retirement savings.

Why do tax advantages favor employees of large employers...

It seems that large businesses have been more effective at influencing legislators despite that there are more people are employed by small than large businesses.
Answer: IRAs were invented to help individuals save for retirement.
401(k)s were invented to help corporations provide more compensation to highly valued employees.
Answer: The investments offered in 401K are usually limited to a selection of mutual funds offered by a 401K provider.  The 401K providers and the mutual funds charge fees.  The mutual fund industry has a lobbying group that will push for increased 401K contributions to direct money into their mutual funds to collect fees.  The top 401 K provider in 2005 was fidelity.  It managed $337 billion in 401Ks of which $334 billion was directed into mutual funds.
Although I would have to use some of the same providers to open an IRA, I would not have to invest in the providers' mutual funds when I open an IRA.  I can buy a stock and hold onto it for 10, 20, 50 years inside of my IRA.  Thus, the only fee the investment company would collect from me would be from when I purchased the stock and when I sold the stock.  Not nearly as profitable as mutual fund fees.
Comment: I can't find any factual basis to your claims. As it has been mentioned numerously on this site, 401k fees in many cases are significantly lower than comparable investments costs outside of a 401k account. Until very recently, IRA accounts charged value-based fees as well (and some still do). As usual with you, unrelated rants with little, if any, factual basis.


How to change Starbound character difficulty?

Question: I made a character and the difficulty I selected doesn't suit me anymore. How do I change it?
Answer: You can't change the difficulty by design after you create the character. But if you don't mind cheating these official rules, you can find your character save file in this folder (or its equivalent in other OSes):
C:\Program Files (x86)\Steam\steamapps\common\Starbound\storage\player

Open the desired player file (you can figure out which one you want by looking at last modified date) with Notepad++ or a similar text editor which lets you see the special characters. Difficulties will look like this:

Note the ACK in Casual difficulty. This special character is important because it won't work if you just type "casual" in a regular text editor and leave the invisible BS before it. The game won't recognize the player file, but it won't delete it. You can just edit back or use Notepad++ to fix this.
Comment: Notepad++ has a free Hex editor plugin available through its built-in plugin manager. But in this case it's more convenient to just create a new character on a different difficulty and copy over that special character into the target save file.
Comment: When it comes to manually editing save games, it's usually a better idea to just use a hex editor instead of a text editor. I personally like Hex Workshop, but it's not free, so I recommend trying HxD. https://mh-nexus.de/en/hxd/
Answer: In addition to savegame hacking, there are also various mods available which enable/disable certain difficulty-specific features.
For example, there are mods which enable hunger on casual difficulty or disable pixel and/or item dropping on death. So when there is one specific aspect of the difficulty level you've chosen which bothers you, you can change that one aspect through modding.