A Version Control System (VCS) allows to organize changes to file structures in unique revisions (aka commits), that save the author, date, optional documentation and the actual changes made.
Working with Version Control makes it possible to work with / speak of specific revisions and reference them as consistent snapshots in time. A feature that underlies any modern Deploy Pipeline and enables Automated Release.
Further, the nature of (especially distributed) VCS supplements collaborative software development in various workflows.
The most widely used VCS is Git - originally written by Linus Torvalds - which underlies the offerings of GitHub. Also widely used are Mercurial, Bazaar and formerly Subversion.
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