title: Trying to understand Open GL
body: <p>I am reading the Open GL ES guide provided by Apple but I don't understand it in full detail and have a question. I am very grateful if you help me understand. On page 28, the chapter about drawing, it says the following:</p>
  
  <blockquote>
    <p>To correctly create a framebuffer:</p>
    
    <ol>
    <li>Create a framebuffer object.</li>
    <li>Create one or more targets (renderbuffers or textures), allocate storage for them, and attach each to an attachment point on the
    framebuffer object.</li>
    <li>Test the framebuffer for completeness.</li>
    </ol>
  </blockquote>
  
  <p>My question is: In point 2, shouldn't it say "create one or more <em>sources</em>..."? As I currently understand it, the frame buffer is what will be rendered to the screen in my draw method. Therefore it would make sense to me if we specify what images we want to have rendered by attaching them to the frame buffer. Clearly, I am misunderstanding something fundamental since in what I describe, the target is the screen and everything else is a source.</p>