title: What is "Call By Name"?
body: <p>I'm working on a homework assignment where we are asked to implement an evaluation strategy called "call by name" in a certain language that we developed (using Scheme). </p>
  
  <p>We were given an <a href="http://www.scala-lang.org/node/138" rel="noreferrer">example in Scala</a>, but I don't understand how "call by name" works and how it is different to "call by need"?</p>