title: Can someone explain Ruby's use of pipe characters in a block?
body: <p>Can someone explain to me Ruby's use of pipe characters in a block? I understand that it contains a variable name that will be assigned the data as it iterates. But what is this called? Can there be more than one variable inside the pipes? Anything else I should know about it? Any good links to more information on it?</p>
  
  <p>For example:</p>
  
  <pre><code>25.times { | i | puts i }
  </code></pre>