Commit
On GitHub, saved changes are called commits. Each commit has an associated commit message, which is a description explaining why a particular change was made. Commit messages capture the history of your changes, so other contributors can understand what you’ve done and why.
Commit & push
Make any change in the code editor and you will notice that an up arrow is displayed on the GitHub button. The arrow means that there are changes are local. They stored on your computer and they need to get saved to GitHub. Click on that button to open the GitHub view.
The GitHub view contains the diffs that represents every local change. If the changes look good, click on commit & push changes to create a commit and push to GitHub. Once the commit is pushed, all your code is safely stored in GitHub!