title: Advantage of "bundle exec rails server" over a simple "rails server"?
body: <p>I bought <a href="http://pragprog.com/book/jvrails/crafting-rails-applications" rel="nofollow">Crafting Rails Applications</a> this weekend and noticed that the author uses</p>
  
  <pre><code>bundle exec rails server
  </code></pre>
  
  <p>to start the development server. What's the advantage of using this command over a simple "rails server"? Is it simply to keep gem dependencies under control?</p>