Git lets you use branches to test new features/code while keeping a clean record on the main master branch. This functionality is great: if the experimental feature is unsuccessful, it doesn't effect the copy on the master branch; otherwise, if successful, it can be merged back into the master branch.
To create a local git repository, run git init in the desired directory. To add or update files in the local repo, first use git add <filename> to add individual files or git add . to add all files (excluding those in .gitignore). This moves the updated files into the staging area and you can check the status using git status. Then, commit these changes to the local repo using git commit -m <message> and you can check commit history with git log.
To collaborate, you would want to set up a remote repository on GitHub. To update the files on the remote repo, use git push. To update your local repo (e.g. when a collaborator has edited something in the remote repo), use git pull. Be sure to use git pull before git push, and if there is a conflict, you may need to merge the code before pushing onto the remote repo.
List the directories and files (e.g. big data files, private info/keys, virtual environment directory, etc.) that you don't want to track with git in a file named .gitignore.
GitHub: Remote Repositories
GitHub is really popular for hosting remote Git repositories. Create an account on GitHub: