title: Understanding a Large, Undocumented Set of Source Code?
body: <p>I have always been astonished by <a href="http://www.winehq.org/" rel="noreferrer">Wine</a>. Sometimes I want to hack on it, fix little things and generally understand how it works. So, I <a href="http://www.winehq.org/download/" rel="noreferrer">download the Wine source code</a> and right after that I feel overwhelmed. The codebase is huge and - unlike the Linux Kernel - there are almost no guides about the code.</p>
  
  <p>What are the best-practices for understanding such a huge codebase?</p>