Technically, a word that is formed by combining some parts (usually the first letters) of some other terms. For example, modem is the acronym derived from modulator/demodulator. In everyday speech, the term is also used to refer to initialisms, which are combinations of letters representing a longer phrase. For example, CRT is an initialism for cathode ray tube. The difference is that an acronym is pronounced as if it were a word rather than just a series of individual letters.
Newsgroups, chat rooms, and e-mail have spawned a rich set of acronyms and initialisms for common phrases. A few of the more common ones are listed below.
