title: How to organize additional project material separately with Git?
body: <p>I want all project files like source code to be part of the repository. For simplicity reasons all work is done on the <em>development</em> branch. Furthermore, I want to include additional project material like pdf files. I do not want to add them to the <em>development</em> branch. Until now I came up with the following strategies.</p>
  
  <ul>
  <li>Strategy 1 is to create a separate branch <em>material</em> and add the pdfs. The branch shares some history with its parent branch.</li>
  <li>Strategy 2 adapts the first strategy but also merges the commits of the <em>material</em> branch into the <em>development</em> branch from time to time. (I do not want this, and it is a pita.)</li>
  <li>Strategy 3 is to create an <a href="https://stackoverflow.com/questions/1384325/in-git-is-there-a-simple-way-of-introducing-an-unrelated-branch-to-a-repository/4288660#comment-7314440">orphan branch</a> that does not share the history of the source code, for example.</li>
  <li>Strategy 4 is to follow strategy 1 or 3 and additionally create a submodule that represents only the <em>material</em> branch of the "main" repository. If this is possible the working directory would show the <em>development</em> branch and the <em>material</em> branch at the same time.</li>
  </ul>
  
  <p>The disadvantage to all strategies is that I can not access the files in the working directory when I checked out another branch.<br>
  How can I work on the <em>development</em> branch and at the same time have the <em>material</em> available in the working directory? If it is easier to you to imagine, the <em>material</em> could also be the <em>documentation</em>.</p>
  
  <hr>
  
  <p><strong>Edit:</strong> I added strategy 4. after reading <a href="https://stackoverflow.com/users/719673/seth-robertson">Seth Robertson</a>'s answer.</p>