Question

$('body > div').each(function() {
...
});

What functionality does comparing body > div provide?

This is a part of answer provided to this question
Comparing DOM elements with jQuery
.
I want to do similar thing but I am not able to understand the functionality provided by comparing two DOM objects.

Answer 1

That’s not a comparison. It’s a child selector. What it does is this:

Selects all direct child elements specified by “child” of elements
specified by “parent”.

So if you have HTML like this:

<div>
    <span>A span</span>
</div>
<div>
    <p>
        <span>A span</span>
    </p>
</div>

Then $("div > span") will select the first span, because it’s a child of a div, but it won’t select the second, because that’s a child of a p.

Note that removing the child selector, and using $("div span") will select both span elements, because that looks for span elements that are descendants of a div, not specifically children.