title: What is a Git Revision Expression?
body: <p>So, I am using Git GUI to make a repository. But I cant find ANY trace on Google, the Documentation, or anywhere else what a 'Revision Expression' is, and it is required to create a new Branch. </p>
  
  <p>Also, it seems that this is used many other places in the program, so I belive it is important to know.</p>
  
  <p>I did find a question on this on StackOverflow, but the guy never got an answer. </p>
  
  <p>I just need to know: What is a Revision Expression?</p>