Editor war is the common name for the rivalry between users of the Emacs and vi (Vim) text editors. The rivalry has become a lasting part of hacker culture and the free software community.
The Emacs vs vi debate was one of the original "holy wars" conducted on Usenet groups, with many flame wars fought between those insisting that their editor of choice is the of editing perfection, and insulting the other, since at least 1985. Related battles have been fought over operating systems, programming languages, version control systems, and even source code indent style. Notably, unlike other wars (ie, UNIX vs ITS vs VMS, C vs Pascal vs Fortran), the editor war has yet to be resolved with a clear winner, and the hacker community remains split roughly 50/50.
The most important differences between vi and Emacs are presented in the following table:
Frequently, at some point in the discussion, someone will point out that ed is the standard text editor.
The Church of Emacs, formed by Emacs and the GNU Project's creator Richard Stallman, is a parody religion. While it refers to vi as the "editor of the beast" (vi-vi-vi being 6-6-6 in Roman numerals), it does not oppose the use of vi; rather, it calls proprietary software anathema. ("Using a free version of vi is not a sin but a penance.") The Church of Emacs has its own newsgroup, alt.religion.emacs, that has posts purporting to support this belief system.