Wrapping a file with (function() { … }).call(this) versus a call with simply ()
<p>The backbone.js source code uses a function wrapper like this:</p>

<pre><code>(function(){
    ...
}).call(this);
</code></pre>

<p>as seen at <a href="http://backbonejs.org/docs/backbone.html#section-185" rel="nofollow">http://backbonejs.org/docs/backbone.html#section-185</a>.</p>

<p>Much more often, I've seen the following used instead:</p>

<pre><code>(function(){
    ...
})();
</code></pre>

<p>When does the behavior of these two differ? I was under the impression that they were equivalent, but I assume that there must be a difference given that Backbone uses <code>.call(this)</code> instead of the shorter alternative.</p>
