According to jQuery.com -
They couldn't of been more dead-on.
I have been using jQuery for quite a few years now and I must say, what a life saver! In its current form, compressed, it weights in at about 32kb and what a 32kb it is. Packed in that small package is a way of doing things that has, without argument, revolutionized web design in a way that I have never seen. It allows for the selecting of elements as easy as a short statement consisting of an absolute minimum of code. It is cross platform stable so no more browser detection and custom code creation to suit. It takes care of that all behind the scenes.
To use, first download it from jQuery.com and place it in your scripts/ folder or somewhere else for easy reference from your HTML document.
Use the following code to implement in your web page:
The above code can be inserted in your document either in the head or in the body of your website though it is recommended to be in the head. It MUST be located prior to any other script that references it.
I'm not going to get to deep into the basic usage here, they have already done a wonderful job of that over at jQuery. Instead in future articles we'll talk about some task specific examples.