title: In ruby how to use class level local variable? (a ruby newbie's question)
body: <p>So suppose I have this (not working): </p>
  
  <pre><code>class User
     description = "I am User class variable"
     def print
         puts description
     end
  end
  </code></pre>
  
  <p>So, how should I use the var description, how to pass this into a method as a default parameter, or used in the method directly? Thanks..</p>