Here is a screen capture of one such version control system called Gitkraken: Image Courtesy GitKraken ... always have all the versions of your source code at your disposal.

an open source distributed version control system for tracking changes in source code during software development. Although Git is designed to help coordinate work among programmers, Git version ...

Mercurial, which is built primarily in Python, was originally created by Matt Mackall to provide a version control solution for managing the Linux kernel source code during the kernel's transition ...