title: How can I switch my git repository to a particular commit
body: <p>In my git repository, I made 5 commits, like below in my git log:</p>
  
  <pre><code>commit 4f8b120cdafecc5144d7cdae472c36ec80315fdc
  Author: Michael 
  Date:   Fri Feb 4 15:26:38 2011 -0800
  
  commit b688d46f55db1bc304f7f689a065331fc1715079
  Author: Michael
  Date:   Mon Jan 31 10:37:42 2011 -0800
  
  commit b364f9dcec3b0d52666c4f03eb5f6efb7e1e7bda
  Author: Michael
  Date:   Wed Jan 26 13:33:17 2011 -0800
  
  commit 4771e26619b9acba3f059b491c6c6d70115e696c
  Author: Michael 
  Date:   Wed Jan 26 11:16:51 2011 -0800
  
  commit 6e559cb951b9bfa14243b925c1972a1bd2586d59
  Author: Michael 
  Date:   Fri Jan 21 11:42:27 2011 -0800
  </code></pre>
  
  <p>How can I roll back my previous 4 commits locally in a branch?
  In other words, how can I create a branch without my latest 4 commits (assume I have the SHA of that commit from git log)?</p>