1 Introduction
jQuery is a JavaScript library of JavaScript is encapsulated, JavaScript programming simplification, improved development efficiency
2. Three versions
1.x: compatible with ie6 / 7/8, commonly, only official bug maintenance functions are no longer new
2.x: not compatible with ie6 / 7/8, the official bug only maintenance functions are no longer new
3.x: not compatible with ie6 / 7/8, only supports the latest browser does not support many of the old jQuery plugin
3. jQuery import
<script src="xxxx/jquery-x.x.x.js"></script>