$ Is jQuery another name
JQuery and jQuery is a function provided by the library. (Seems not just function because such use as well as $ .ajax (options), equivalent jQuery.ajax (options))
This function returns the find and select html elements of the document is one of a function of the role of substitute, GetElementByID according to () in the parameters, but () is not only within the ID, can be all kinds of selectors
such as:
$ (Document) is to select the entire document object
It is not only can be used to replace the $ is not. In order to prevent naming conflicts, jQuery library provides additional mechanisms to give jQuery function from another alias.
E.g:
var FAccount = $("#FAccount").val();
Find ID = FAccount value is on the last of the program '