jquery and $

And jquery is a function provided by the jquery library. (It seems that it is not just a function, because there is also the use of $.ajax (options), equivalent to Jquery.ajax (options))

The function is to find and select the elements in the HTML document according to the parameters in the (), one function is to replace the getElementById, but () can not only be the ID, but also a variety of selectors

Like what:

$ (document) is the selection of the entire object

That is not only can be replaced with $, not. To prevent naming collisions, the jquery library provides additional mechanisms to alias the jquery function.

For example:

var j = jquery.noconflict (); //do something with JQuery j (). Hide (); //do something with another library ' S $ () $("content").style.display = ‘none‘;

You can use JQ instead of jquery and $ in your code.