It's not a good idea to multitask when working. However, some projects just
need it. The reason can be multiple features you are developing in parallel or
more than one guy working on the project. To keep track of different changes
-that are realated the concept of branches was introduced.
+that are related, the concept of branches was introduced.
Branch is just alternative history that can be merged one day back to the main
history. The main history branch is named `master` by default.