title: iOS: Audio Units vs OpenAL vs Core Audio
body: <p>Could someone explain to me how OpenAL fits in with the schema of sound on the iPhone?</p>
  
  <p>There seem to be APIs at different levels for handling sound. The higher level ones are easy enough to understand.</p>
  
  <p>But my understanding gets murky towards the bottom.  There is Core Audio,  Audio Units, OpenAL.</p>
  
  <p>What is the connection between these?  Is openAL the substratum,  upon which rests Core Audio (which contains as one of its lower-level objects Audio Units) ?</p>
  
  <p>OpenAL doesn't seem to be documented by Xcode,  yet I can run code that uses its functions.</p>