title: check whether array contains every element of another array or not
body: <p>I want to check if given array contains every single element of second array for example</p>
  
  <pre><code>['Laptop', 'PC', 'Ipad', 'Telephone', 'Smart Watch']
  ['Laptop,' 'PC', 'Smart Watch'] //true
  ['Laptop', 'Ipad', 'Banana'] //false
  </code></pre>
  
  <p>I tried this code:</p>
  
  <pre><code>var arr = [1, 2, 3];
  var check = [3, 4, 5];
  
      var found = false;
        for (var i = 0; i &lt; check.length; i++) {
            if (arr.indexOf(check[i]) &gt; -1) {
               found = true;
               break;
            }
        }
      alert(found);  
  </code></pre>
  
  <p>It works but not as i want, it alerts true even if only one element from child is found in parent array. so how can i implement what i want?</p>