title: Git checkout - switching back to HEAD
body: <p>I've been doing my project while at some point I discovered that one thing stopped working. I needed to look up the state of my code when it was working correctly, so I've decided to use git checkout (because I wanted to check-something-out). And so I've done</p>
  
  <pre><code>git checkout SHA
  </code></pre>
  
  <p>couple times while going back to point from which I can't go to HEAD, the output is following:</p>
  
  <pre><code>git checkout SHA-HEAD
  
  error: Your local changes to the following files would be overwritten by checkout:
      [list of files]
  Please, commit your changes or stash them before you can switch branches.
  Aborting
  </code></pre>
  
  <p>I am pretty much sure I have NOT changed anything. The command</p>
  
  <pre><code>git checkout master
  </code></pre>
  
  <p>gives the same output.</p>
  
  <p>Is there a way to go back to HEAD?</p>
  
  <p>What is the safe way of "jumping over" history commits?</p>