Emacs

Emacs is a class of text editors that have an extensive set of features and that are popular with computer programmers and other technically proficient computer users.

GNU Emacs, a part of the GNU project, is under active development and is the most popular version. The GNU Emacs manual describes it as "the extensible, customizable, self-documenting, real-time display editor." It is also the most portable and ported of the implementations of Emacs. As of 2007, the latest stable release of GNU Emacs is version 22.1. XEmacs is the other major Emacs.

The original EMACS was a set of Editor MACroS for the TECO editor written in 1975 by Richard Stallman, initially together with Guy L. Steele, Jr.. It was inspired by the ideas of TECMAC and TMACS, a pair of TECO-macro editors written by Steele, Dave Moon, Richard Greenblatt, Charles Frankston, and others.citation needed] Many versions of Emacs have appeared over the years, but two are now commonly used: GNU Emacs, started by Stallman in 1984 and still maintained by him, and XEmacs, a fork of GNU Emacs started in 1991 that has remained mostly compatible. Both use a powerful extension language, Emacs Lisp, that allows them to handle tasks ranging from writing and compiling computer programs to browsing the web.

In Unix culture, Emacs is one of the two main contenders in the traditional editor wars, the other being vi.

Some people make a distinction between the capitalized word "Emacs", used to refer to editors derived from versions created by Stallman, and the lower-case word "emacs", used to refer to the large number of independent emacs reimplementations. The word "emacs" is often pluralized as emacsen (by analogy with boxen and VAXen).