Backing Up Code
Code finds a way of getting wrecked at the worst times. Somehow you delete the files, your computer dies, you accidentally replace all code with a load of letters, computer is stolen, and many more are all reasons you could lose code. Replacing a computer is easy, replacing the work on the computer is not.
Multiple versions of your work. You can see how things change over time.
Allow for Teamwork
Branches and merging can really help work on one piece of code at once.
Encourages documentation and documenting
Keep in mind that everything on Git is public unless you make it private. You should not include any sensitive information.