One frequently used feature of Git is the ability to amend to a commit. This is possible because, in Git, there is a difference between creating and publishing a commit. This won't inconvenience users compared to CVS, where it would. If you make a typo in your commit message in Git, you can use git commit --amend to correct it. It's also technically possible in CVS, but it would be hard to implement:

 $ echo "This is the last line FOR REAL" >> README.md
 $ git log
 commit 499beb6dd81ee62e90b05ee8e9aa3ccced7a4fd2 (HEAD -> new-readme)
 Author: Joost Evertse <[email protected]>
 Date:   Thu Dec 6 21:18:32 2018 +0100
 
    A new line was added

Let's pretend I forgot to add something to my README.md file (a text file in my repository). The following code shows you how to add it to the last commit:

 $ echo "This is the last line FOR REAL" >> README.md
 $ git add README.md
 $ git commit -m "A new line was added FOR REAL" --amend
 $ git log
 commit 9c527dfe0ac2ce04b6cd1be6085bac00c7f31e6c (HEAD -> new-readme)
 Author: Joost Evertse <[email protected]>
 Date:   Thu Dec 6 21:18:32 2018 +0100
 
    A new line was added FOR REAL

By doing this, you can add to a commit, but this is only reflected in your local Git copy. You still have to push your changes to remote servers if you want others to see your changes.