Git checkout
git checkout moves you to another branch or commit, and updates the files in your working directory to match.
With -b it creates a new branch and moves to it in one step. Newer versions of Git also have git switch for branches and git restore for files, which are easier to read.
Move to a branch
git checkout hello-world-images
Switched to branch 'hello-world-images'
Create a branch and move to it
git checkout -b emergency-fix
Switched to a new branch 'emergency-fix'