title: How do I move the contents of my master branch to a new Git branch?
body: <p>I've been making some vast changes on the master branch of my Git repository. I'm pretty new to Git and so I'm wondering:</p>
  
  <p>How can I move my current master branch to a new branch and recreate my master branch from scratch for a particular folder of files?</p>
  
  <p>As an example, I have another folder, like <code>new_stuff</code>, that contains the new files to be added to the master branch, and that old master is a new branch named <code>old_master</code>.</p>