title: Why did git keep the files after I changed back to master?
body: <p>I was working in a branch that I created like:</p>
  
  <pre><code>git checkout -b feature_xyz
  </code></pre>
  
  <p>After working in that branch, I wanted to throw away all the work so I moved back to master:</p>
  
  <pre><code>git checkout master
  </code></pre>
  
  <p>When I did that, I saw this:</p>
  
  <p>M  app/path/to/file1.rb
  M  app/path/to/file2.rb
  D  app/path/to/file3.rb
  switched to branch 'master'
  your branch is up-to-date with origin/master</p>
  
  <p>I then deleted the feature branch:</p>
  
  <pre><code>git branch -d feature_xyz
  </code></pre>
  
  <p>Now when I do git status I see files that I was modifying in that feauture_xyz branch, how is this possible?</p>