The word 'acronym' (from the Greek acro meaning summit, and onym meaning name) means a pronounceable name made up of the initial letters of the thing it describes: for example, the United Nations Education, Science and Cultural Organisation - UNESCO.

A Capital Idea

Acronyms are a handy way of abbreviating the alphabet soup which is science, technology and politics; instead of having to pronounce either the names of the letters (as in GWR - Great Western Railway) or the full name of the organisation or object, we have a single short word. Occasionally we may miss out the definite article ('the'), or use the second letter as well as the first letter of a word, as with RADAR (RAdio Detection And Ranging).

There is a problem, though. The world has now reached a point of craziness where a key criterion for certain types of grant application is that you must have a snappy acronym for your project. The UK's science funding body will not accept proposals without an acronym. This can result in the name of the project being designed specifically to provide a nice acronym - a classic case of the tail wagging the dog.

To geeks this is known as being 'YABA compatible'. YABA is an acronym standing for 'Yet Another Bloody Acronym', used by those who consider that twisting project names just so they form a nice acronym is a complete WOMBAT (Waste Of Money, Brains And Time). The letters YA in computer acronyms usually resolve to 'Yet Another', such as:

• YACC - Yet Another Compiler Compiler
• YAUN - Yet Another Unix Nerd - this term is used on Usenet, as <YAUN> in response to tedious pro-UNIX posts

A true acronym should be written all in upper case (UNESCO, NATO, NORAD, for example) but as they pass into the language they occasionally take on the case of a proper noun - although many of those spelled this way are simply backronyms, of which more later.

As usual, the study of boundary conditions improves understanding. So, a word which lies on the border between acronyms and initials is EBCDIC (Extended Binary Coded Decimal Interchange Code) - this is only just pronounceable ('eb-suh-dik'), but many people recite the letter names instead.

The Three-letter Acronym (TLA)

In the computer industry, laziness combines with invention to produce some of the shortest possible acronyms: those comprising just three letters. With deliberate irony these are known as TLAs - Three Letter Acronyms. Except for the most part they aren't acronyms at all. They are simply abbreviations. So TLA really means a Three Letter Abbreviation; thus itself becoming a TLA.

The Numerical Algorithms Group produced a library of standard Fortran routines known as the NAG library. That's a genuine TLA, as is GNU (see below), DIP (Dual Inline Package, the little switches on processor boards) and GUI (pronounced 'gooey'), because they are all pronounceable. But note that the most common definition of TLA is still 'Three Letter Acronym' - and as such it is mis-applied in the vast majority of cases (PCI, VGA, CGI - more, indeed, than you can poke a stick at).

The Enhanced Three Letter Acronym (ETLA)

There are only so many combinations of three letters. Some concepts require four or more, and some wag christened these ETLAs or Enhanced (some prefer 'Extended') Three Letter Acronyms. The American Standard Code for Information Interchange (ASCII) is a good example. Yes, yes, that's just a common or garden acronym. That's the point - it's humour.

This reached its illogical conclusion in a piece of technology from the Personal Computer Memory Card International Association, PCMCIA. An ETLA, you will notice, of six letters (and not a pronounceable word, so not actually an acronym). But nobody could remember what it stood for, so it became 'People Can't Memorise Computer Industry Acronyms'.

Backronyms

A backronym is a name which was originally just that, but from which a (rarely convincing) acronym has been developed. The Apple Lisa, a precursor to the Macintosh was actually named after Steve Jobs' (co-founder of Apple and current CEO) daughter, but later said to be the acronym 'Local Integrated Software Architecture'. A classic backronym.

The computer language BASIC (Beginner's All-purpose Symbolic Instruction Code) is said to be a backronym, but the evidence is inconclusive. While the language C was definitely a progression from APL (A Programming Language), BASIC may always have been acronymic, rather than just a basic programming language.

A personal favourite of many Researchers is the scanner interface standard called Twain. This was actually taken from Kipling: '... and never the twain shall meet', but the preponderance of TLAs and ETLAs in the computer industry led people to assume it was an acronym. This was exacerbated by the arbitrary decision of the TWAIN standards organisation to start spelling it in all uppercase. What could it stand for? A competition was started, and an urban legend was born: 'Technology Without An Interesting Name'. A false backronym. The same applies to the army term Grunt (a term of abuse for infantry troops) which is said to stand for 'Ground Reconnaissance Unit, Non-Thinking' - but of course doesn't. Probably.

Recursive Acronyms

A supremely elegant form of acronym is the recursive, or self-referencing acronym. This is hard to do convincingly and there are not many examples. The best known is probably the UNIX term GNU - 'GNU's Not Unix'; this was originally a free-distribution UNIX replacement project, but became attached to a software licensing system, the GNU Public License, whereby open source code can be included in other code provided the open source license comes with it - in other words, we'll show you ours if you show us yours. This was described by Microsoft as a 'viral' licensing system until it was pointed out to them that several of their own products included GNU licensed code.

An early recursive acronym, dating back to the early 1960s, is Mung: 'Mung Until No Good', the process of rewriting a large and complex piece of code until it becomes both unrecognisable and dysfunctional. This was originally 'Mash Until No Good', but the meaning changed over time. Its invention is thought to have been inspired by the wartime US Army term for a form of bully beef, which was spelled 'mung' but as often as not pronounced 'munge', which comes from the Scottish dialect.

Abbreviated Conclusion

In the way of the English language throughout history, the word acronym will probably be redefined as being syntactically equivalent to 'abbreviation'; until then an acronym is only an acronym if you can pronounce it as a word.

A good source of information on TLAs and ETLAs is the (gratifyingly acronymic) FOLDOC - the Free On Line Dictionary Of Computing.