You can view the available Emacs branches at http://bzr.savannah.gnu.org/r/emacs/ Development normally takes places on the trunk. Sometimes specialized features are developed on separate branches before possibly being merged to the trunk. Development is discussed on the emacs-devel mailing list. Sometime before the release of a new major version of Emacs (eg 23.2), a "feature freeze" is imposed on the trunk. No new features may be added after this point. This is usually some months before the release. Shortly before the release, a release branch is created, and the trunk is then free for development. For example, "emacs-23" for Emacs 23.2 and later, "EMACS_23_1_RC" for 23.1, "EMACS_22_BASE" for 22.x, and "EMACS_21_1_RC" for 21.x. Consult emacs-devel for exactly what kinds of changes are allowed on what branch at any time. If you are looking at this file in a branch other than the trunk, there may be some branch-specific documentation below this line. ________________________________________________________________________ * elpa This branch does not contain a copy of Emacs, but of the Emacs Lisp package archive (elpa.gnu.org). See admin/notes/elpa for further explanation, and the README file in the branch for usage instructions.