Introduction to jQuery selectors
Because this is such a common task, the jQuery constructor comes in several forms that takes a selector query as an argument, allowing you to locate element(s) with a very limited amount of code for optimal efficiency. You can instantiate the jQuery object simply by writing jQuery() or even shorter using the jQuery shortcut name: $(). Therefore, selecting a set of elements is as simple as this:
With the jQuery object returned, you can then start using and altering the element(s) you have matched. In the following chapters, you will see examples of some of the many ways you can select elements with jQuery.