title: What's the use of <> in Perl?
body: <p>What's the use of &lt;> in Perl. How to use it ?
  If we simply write</p>
  
  <pre><code>&lt;&gt;;
  </code></pre>
  
  <p>and </p>
  
  <pre><code>while(&lt;&gt;)
  </code></pre>
  
  <p>what is that the program doing in both cases?</p>