title: Javascript Filter integers
body: <p>I'm learning javascript on FreecodeCamp. And, the solution of my problem doesn't help me more.
  We have to filter integers in an array which is saved in const variable.</p>
  
  <pre><code>const realNumberArray = [4, 5.6, -9.8, 3.14, 42, 6, 8.34, -2];
  const squareList = (arr) =&gt; {
    "use strict";
  const squaredIntegers = arr.filter( (num) =&gt; num &gt; 0 &amp;&amp; num % parseInt(num) === 0 ).map( (num) =&gt; Math.pow(num, 2) );
   return squaredIntegers;
  };
  
  const squaredIntegers = squareList(realNumberArray);
  console.log(squaredIntegers);
  </code></pre>
  
  <p>and I cannot understand really this part <code>num % parseInt(num) === 0 ).map( (num) =&gt; Math.pow(num, 2) );</code></p>
  
  <p>Why using parseint() method and Math.pow. Someone could explain me why?</p>
  
  <p>thanks.</p>