title: Ruby - LoadError on require
body: <p>I have the following two files: <code>main.rb</code> and <code>sort.rb</code> located in the same folder. In <code>main.rb</code> I have the following code:</p>
  
  <pre><code>require 'sort'
  
  Sort.insertion_sort([1,2,3,4]).each {|x| print "#{x}, "}
  </code></pre>
  
  <p>When I try and run this via ruby <code>main.rb</code> I get the following error:</p>
  
  <pre><code>&lt;internal:lib/rubygems/custom_require&gt;:29:in `require': no such file to load -- sort (LoadError)
      from &lt;internal:lib/rubygems/custom_require&gt;:29:in `require'
      from main.rb:1:in `&lt;main&gt;'
  </code></pre>
  
  <p>Any ideas why?
  Thanks</p>