Mercurial is a fast, lightweight Source Control Management system designed for efficient handling of very large distributed projects. A distributed SCM tool is designed to support a model in which each Repository is loosely coupled to many others. Each Repository contains a complete set of metadata describing one or more projects. These repositories may be located almost anywhere. Individual developers only need access to their own repositories, not to a central one, in order to commit changes. Changes can be share via the builtin webserver, CGI, SSH or a stream of patch emails. Mercurial supports Apples' FileMerge for merges.

WWW: https://www.mercurial-scm.org
