Git branch is actually a commit node tree.

Let’s make a vivid visualization

After finishing the commit, that newly created commit will be placed on the HEAD.

You could create a new branch based on a existing branch.

git checkout -b Development

Now you can commit on the Development branch

We can go back to the master branch and continue commiting on master branch

git checkout master

We can create another branch

git checkout -b other

And still checkout the master branch again

git checkout master

As you can see HEAD pointer is a special branch name that always point to the current branch or commit that we are working on.