What is the use of function.call method?
<pre><code>var x = 10;
var o = { x: 15 };

function f()
{
    alert(this.x);
}

f();
f.call(o);
</code></pre>

<p>The first one would display me '10' and the second one would display '15' as output value. Can anyone tell in which real time scenario i would use the 'call' method and also the f() at the same time.</p>
