title: Ruby on Rails: Modules vs. Classes
body: <p>I'm trying to add a function that will be accessible throughout all parts of my program.  I want something like:</p>
  
  <pre><code>def GlobalFunctions.my_function(x,y)
      puts x + y
  end
  </code></pre>
  
  <p>to be accessible for all models.  Specifically I am trying to use a function like this in my seeds.rb file but I am most likely going to be reusing the code and don't want any redundancy.  Now I know I can make a simple class, but I could also make a module.  What are some reasons to go in either direction? And once I've decided on which type to use, how do I make it accessible throughout the whole program?</p>
  
  <p>I have tried a module, but I keep getting " Expected app/[module file] to define [ModuleName]"</p>