What is difference between assigning NULL and unset?
<p>take a look in following code:</p>

<pre><code> &lt;?php 
   $a = 20;
   $a= NULL;  //or unset($a)
   if(isset($a))
   {
      print("hi");
   }
   else
   {
       echo "not initiated";
   }
   if(isset($b))  //$b is a variable which is not initialized
   {
       print("hi");
   }
   else
   {
       echo "not initiated";
   }

?&gt;
</code></pre>

<p>and when apply unset, i get the same result:</p>

<p>So, What is difference between assigning NULL and unset?</p>
