title: What is "Argument-Dependent Lookup" (aka ADL, or "Koenig Lookup")?
body: <p>What are some good explanations on what argument dependent lookup is? Many people also call it Koenig Lookup as well.</p>
  
  <p>Preferably I'd like to know:</p>
  
  <ul>
  <li>Why is it a good thing?</li>
  <li>Why is it a bad thing?</li>
  <li>How does it work?</li>
  </ul>