[Turn]jquery the difference between descendants and child elements

This is what's in "the Sharp jquery" book.

<div>    <p>        <span></span>        <a></a>        <b></b>    </p></div>

P is a sub-element of the Div, span is a child of P, and a, B is also a child of P

P is the descendant element of the Div, and span, a, b are the descendant elements of the Div

Descendants can be thought of as all elements contained, while child elements are just elements that contain one layer

The above example can be understood as Div is father, p is the son of Div

Span, A, B is the son of P, the div grandson, but all the descendants of Div and P

[Turn]jquery the difference between descendants and child elements