title: Create groups vs Create folder reference in Xcode
body: <p>I'm curious when using Xcode.</p>
  
  <p>I always need to choose an option when copying the open source class files I need for my project.</p>
  
  <p>The options are "Create groups" and "Create folder references".</p>
  
  <p>I've read the difference between the two already.</p>
  
  <p>But it is not understood at all.</p>
  
  <p>When I chose one of the two options, I deleted the file from my project and the open source class file was deleted at the same time.</p>
  
  <p>I do not want it.</p>
  
  <p>I want to always exist as an independent file. What should I choose?</p>