what's the difference between the two ways of writting in jquery?
<p>1,     <code>$.each(a,f);</code></p>

<p>2,<code>$("a").each(f);</code></p>

<p>i know the last line meaning, which represents all <code>&lt;a&gt;</code> elements in the document. Then call the each() method then invoke the function <code>f</code> once for each selected element. but i don't know what's the meaning of the first one? and what's the use of it? thank you.</p>
