title: I have a gem installed but require 'gemname' does not work. Why?
body: <p>The question I'm really asking is why require does not take the name of the gem. Also, In the case that it doesn't, what's the easiest way to find the secret incantation to require the damn thing!?</p>
  
  <p>As an example if I have <code>memcache-client</code> installed then I have to require it using</p>
  
  <pre><code>require 'rubygems'
  require 'memcache'
  </code></pre>