title: Why does "1" in awk print the current line?
body: <p>In <a href="https://stackoverflow.com/a/20243180/34088">this answer</a>, </p>
  
  <pre><code>awk '$2=="no"{$3="N/A"}1' file
  </code></pre>
  
  <p>was accepted. Note the <code>1</code> at the end of the AWK script. In the comments, the author of the answer said</p>
  
  <blockquote>
    <p>[1 is] a cryptic way to display the current line.</p>
  </blockquote>
  
  <p>I'm puzzled. How does that work?</p>