title: Explaining Interfaces to Students
body: <p>For a few years I was a teaching assistant for an introduction to programming module - Java for first year undergraduates.</p>
  
  <p>Mostly it went well and we managed to get object-oriented programming across to the students quite well, but one thing that students rarely saw the point of was interfaces.</p>
  
  <p>Pretty much any explanation we gave either came across as too contrived to be useful for learning, or too far removed from their position as beginners.  The reaction we tended to get was "I... see," translated as "I don't understand and they don't sound useful".</p>
  
  <p>Anyone here have a way of successfully teaching students about interfaces?  I'm not a teaching assistant any more, but it's always nagged at me.</p>