title: How does Delayed Job work in Ruby on Rails ?
body: <p>I am new to this and is little confused about how Delayed Job works ? </p>
  
  <p>I know it creates a table and puts the jobs in the table and then I need to run </p>
  
  <pre><code>rake jobs:work
  </code></pre>
  
  <p>to start the background process. Now my question is</p>
  
  <ol>
  <li><p>Does DJ script checks the table every minute and when the time matches job_at time, it runs that job ? </p></li>
  <li><p>How it is different than cron (whenever gem) if the script is just checking the table every min ? </p></li>
  </ol>
  
  <p>Thanks</p>