title: What does map(&:name) mean in Ruby?
body: <p>I found this code in <a href="http://railscasts.com/episodes/167-more-on-virtual-attributes" rel="noreferrer">a RailsCast</a>:</p>
  
  <pre><code>def tag_names
    @tag_names || tags.map(&amp;:name).join(' ')
  end
  </code></pre>
  
  <p>What does the <code>(&amp;:name)</code> in <code>map(&amp;:name)</code> mean?</p>