Screen name (computing)
A screen name, screenname or s/n is a name or string of characters chosen to uniquely identify a user within an online system, including dial-up bulletin board systems, platform videogame servers, and Internet-based environments. The term started out as screen name (two words), but in recent years, the usage of the single-word form screenname has been steadily increasing. The abbreviation "sn" can also mean screen name in online contexts.
A screen name is frequently limited in length and character composition by the technical restrictions of the applications for which it is used, such as e-mail, instant messaging, or file sharing. For example, Prodigy (ISP) online service originally assigned non-word alphanumeric strings as screen names, and Compuserve online service originally assigned only numeric strings. Screen names are often pseudonyms or first names, many times complemented by extra numbers, letters, or other characters to disambiguate them from users with similar screen names on the same system; this practice is increasingly common as the popularity of online environments grows and the availability of unique identifiers dwindles.
The term 'screen name' was originally coined by the America Online service, and, strictly speaking, does not apply in cases other than usernames for the AOL and AOL-owned CompuServe services. Outside the AOL milieu, it is much more common to use the synonyms 'handle', 'username,' 'user id', or 'nickname' (shortened to 'nick' in the IRC environment).[citation needed] The use of 'screen name' is often used as a reverse shibboleth by old timers to identify those who are newer to the online world.