The TLA (three-letter abbreviation or acronym) is the most popular type of abbreviation in computing and telecom terminology and Internet slang, and is also common in political jargon. Some of these, such as "DOS", are strict acronyms, while others, like "TLA" itself, are initialisms; this distinction is not universally accepted (see the latter article for a discussion), but leads to the use of abbreviation as opposed to acronym in expanding the term.
| Table of contents |
"TLA" is, of course, a TLA itself; the term was almost certainly coined with a certain degree of self-referential humor in mind. Likewise, a four-letter abbreviation (e.g., VERA) is sometimes known as a LFLA (Longer Four Letter Acronym), an ETLA (Extended TLA) or a TLA/E (TLA/Extended). All three terms are of the same humor: the word "LFLA" is an LFLA. In the same vein, VLFLA is a Very Long Five Letter Acronym and DETLA is a doubly-extended three letter acronym, although they are heard less.
TLAs became common in the United States during the New Deal of President Franklin Delano Roosevelt (who was, and still is, himself often referred to as "FDR"). Terms from this period included NRA for National Recovery Administration, and TVA for the Tennessee Valley Authority. Detractors of President Roosevelt's policies called the new agencies "alphabet soup."
Using only upper-case letters, there are 26³ = 17576 possible three-letter abbreviations, and probably most of them are already used in some context. If numbers, special characters, or case-sensitivity are allowed, even more TLAs can be created.
Many TLAs have more than one meaning: TLA itself is also a TLA for the Theatre of the Living Arts (http://www.theateroflivingarts.net). There are many TLAs with more than 10 meanings (for example, SDI has at least 32 meanings in the English language). Furthermore, many abbreviations have more than one expansion with the same meaning. For example GCC was first 'GNU C Compiler', and later 'GNU Compiler Collection'. (See also backronym.)
In the MS-DOS operating system for personal computers, because only three-letter file extensions (usually denoting the file type) were allowed, many longer abbreviations were shortened to three letters (for example JPEG to JPG, HTML to HTM). Many abbreviations, some of them TLAs, come from the shortened names of Usenet groups. For example pra for pl.rec.anime.
A significant number of TLAs come from various codes: