Git is a distributed source control management system that provides speed and data integrity. It was created by Linus Torvalds and allows users to initialize repositories, add and commit files, checkout different versions, create and delete branches, add and push to remote repositories, merge and rebase branches, and squash commits. The document recommends committing often, checking diffs before pushing, branching for all changes, and thinking about the commit history. It provides additional resources for learning Git interactively.