Amend The Last Commit

If you just created a commit and immediately realize the message is wrong, or you forgot to include a file, you can rewrite that commit with:

git commit --amend -m "New message"

This replaces the most recent commit with a new one that has your updated message and includes whatever is currently staged.

To add a forgotten file to the previous commit, stage it first, then amend without changing the message:

git add forgotten.txt
git commit --amend --no-edit

The --no-edit flag keeps the existing message.

One catch: amending creates a brand-new commit (with a new ID), even though it looks like an edit. Only amend commits you have not shared with anyone yet, or you will confuse collaborators who already have the old version.