23.7.1 Introduction to Version Control
VC allows you to use a version control system from within Emacs,
integrating the version control operations smoothly with editing. VC
provides a uniform interface to version control, so that regardless of
which version control system is in use, you can use it the same way.
This section provides a general overview of version control, and
describes the version control systems that VC supports. You can skip
this section if you are already familiar with the version control system
you want to use.