Imagine you are editing your code with a few buddies. You make one change that you think is pretty good, but at the last minute, somebody else uploads their code and it overwrites the code you are writing. To fix this you upload your code, but that overrides everything they did. The solution Git provides is known as branching. You can think of branching much like a tree, where there is one main stream of code (The actual tree) but has small branches (changes) that are independent of the main tree and other branches. The benefit of branching is that by giving each problem its own branch, it can be worked on with its own code. Others can still view and work on your code if they wish, but they do not have to worry about their own problems affecting your branch when they are working on a separate one. Every time you edit something, you should push and commit the changes at the end.

Every repository has a master branch. The master branch is the final version of the code that you should use at a competition. "Pull requests" should happen whenever you want to push to the master branch. You should only push to the master branch when your code is completed and has no issues.