Work on Two Things at Once

Up to this point, all our work has happened on a single line of commits, one after another. That works fine when you're working alone on something simple, but what happens when you want to try out a new idea without risking your working code? Or when two people need to work on different features at the same time?

This is where branches come in. A branch is an independent line of development. You can think of it as a copy of your project where you can make changes freely, without affecting the main version. When you're happy with the result, you merge the branch back in.

We'll keep working with our calculator project: