All-points bulletin

An all-points bulletin (APB) is an electronic information broadcast sent from one sender to a group of recipients, in order to rapidly communicate an important message of high importance. The technology used to send this broadcast has varied throughout time, and includes Teletype, Radio, Computerised Bulletin Board Systems (CBBS), and Internet.
The earliest known record of the all-points bulletin is when used by American police, which dates the term to 1947. Although, used in the field of policing at the time, the APB has had usage in fields such as politics, technology and science research. 
However, since the 21st Century, due to advances in technology, all-points bulletins have become significantly less common and are now only primarily used by police departments in countries such as America, Canada, Australia and the United Kingdom.
Technological functionality in the 21st Century:.
The modern, 21st Century technological evolution of the all-points bulletin is mainly only used in the world of policing. Police officers will use computers, both at the police-station and fitted in their vehicles, connected to a private police intranet, to access APBs. Other forms of media that perform similar functions to APBs include smartphone apps and internet web pages. 
Besides in the field of policing, APBs are almost completely out of use in 21st Century society. Due to the rapid evolution of such internet and other technology beginning in the early 2000s, the all-points Bulletin is becoming an increasingly less useful method of communicating messages, and less information is being published about it. 
The future of the all-points bulletin.
In 2020, established Harvard Professor Jonathan Zittrain published speculations about future evolution of the all-points bulletin. Zittrain argues that in the future, the act of sending out an all-points bulletin will be take the form of “asking millions of distributed scanners to check for a particular identity and summon police if found” (Zittrain, 2020). 
Technological functionality (pre-21st century).
The functionality of all-points bulletins was based on the latest advances in computer networking at the time, developed in the 1940s and continuing evolution through to the 1970s. Different from e-mail or teleconferencing, which are designed for limited list of recipients, all-points bulletins were digital message “broadcast systems” (Rafaeli, 1984). It is described that “each message placed on [an APB] is intended for a wide audience” (Rafaeli, 1984), and they were some of the first technologies which could do so in an efficient and effective manner (Rafaeli, 1984).
Users access these all-points bulletins “through terminals or microcomputers by dialling in over dedicated or general-purpose telecommunication lines.” (Rafaeli, 1984). The APB then show messages that will be readable for the users of the system, and in some systems, users are able to attach their own messages similar to a virtual bulletin board. Consequently, messages would not only be able to be seen by the sender, but also by subsequent users of the digital bulletin system, who could also add their own information and messages to this bulletin. Users were thus able to build information upon one another, enabling for discussion of ideas and information between individuals in society from despite using different computers in different locations (Garramone et al., 1986).
However, in regard to the technical functionality of the computerised bulletin systems, there is a lack of significant research on the technical construction and development of these terminals and computers. Hence, modern knowledge of the technicalities of these older all-points bulletin systems is restricted.
Policing.
In the field of policing, an all-points bulletin contains an important message about a suspect or item of interest, which officers may be in search for. They are primarily used for individuals are classified as dangerous and for crimes of high priority (Reiter, 1970). In these fields, the APB may also be known as a BOLO, for ‘be on (the) look-out’.
In 1970, Farmville Police department in North Carolina, USA, reported about their implementation of the all-points bulletin (APB) system beginning in 1968 (Reiter, 1968). If stolen car was reported, usually officers would send out a radio broadcast to all patrol cars and to various other stations within a certain radius. In relatively short time, the messaged can be relayed around the state. However, after the introduction of the bulletin, the similar function can be done, but faster. Police can send out an APB that will reach thirteen states, through the use of teletype (Reiter, 1970). Officers also used the APB if they were required to notify individuals about the death of family members.
Other countries.
A similar, longer acronym used by Australian law enforcement is KALOF or KLO4 (for "keep a look-out for"). The United Kingdom uses a similar system known as the all-ports warning or APW, which circulates a suspect's description to airports, ports and international railway stations to detect an offender or suspect leaving the country. Because of the great numbers of commuters at such places, British police forces often prefer to contact specific airports, ports or stations and circulate descriptions individually.
Politics.
All-points Bulletins have been used in politics, where users are able to leave messages, read messages left by others previously, and respond to others’ messages. In 1986, the electronic all-points bulletins were being used by politicians as another means of communicating with voters (Garramone et al., 1986). Politicians would use APBs “to inform constituents about their recent activities and how they stand on selected issues”, improving their “interactive capability” with the electorate. 
Additionally, APBs had functioning two-way communication systems, where voters were able to write messages back to the politicians via the computer keyboard. This enabled voters to respond to politicians about their own stances on certain issues and to engage in digital discussions with one another and also the politicians. This ability to discuss ideas and politics without being in-person was a revolution in politics. Due to this and other “additional unique features”, political APBs simply offered new abilities that platforms traditional media such as newspapers and televisions at the time could not and opened new doors for politicians. However, overall access to political ABSs was very limited, with CompuServe (leading digital APB provider) having 150,000 subscribers and the penetration rate for personal computers reached 14% in 1984 (Levy, 1984).