title: Linux awk command with pipe
body: <p>Can anyone tell me what the below linux command does:</p>
  
  <pre><code>tail -5 test.log | grep 'Start Calculate' | awk '{print $1}'
  </code></pre>
  
  <p>I know <code>tail -5 test.log | grep 'Start Calculate'</code> looks for the 5 last lines containing 'Start Calculate' in test.log. But then I don't get what awk does?</p>