Git has won the race for the most popular version control system. But why exactly is it so popular? The answer, at least in my opinion, is pretty clear: branches! They allow you to keep different versions of your code cleanly separated—ideal when collaborating in a team with other people, but also for yourself when you begin working on a new feature.
Although other version control systems also offer some form of branching, Git’s concept and implementation are just stunning. It has made working with branches so quick and easy that many developers have adopted the concept for their daily work.
Source: A look under the hood: how branches work in Git, an article by Tobias Günther.