How to do a better form post with javascript?

Good afternoon.
We want to make more efficient internal form posts in a Web site have a lot of trafic. With internal posts I am talking about the information the user didn’t introduce directly in this page, I mean, the information is used for the system. My boss told me search if is better use jquery or AJAX for that. By the way, I am learning jquery so please excuse me if I say some wrong think and please lets me know my mistake.
I have been googling but I only saw how to do ajax’s posts through jquery. What do you think is the better option?? Summarizing: we want many of the post happen in the user’s computer. We will be really gratefull for any comment, suggestion, etc.

You can either do ajax calls directly from JavaScript (see for some examples) or you can have JavaScript call jQuery and have the jQuery make the ajax call for you. Either way you are still using the same calls to the server, just that jQuery wraps the code for the call inside a function for you to save you having to write all the code for yourself. Once the code is written it will not matter which of the two you have chosen except that if you use jQuery only for that and don’t make use of the rest of the library then you will have visitors downloading a big chunk of JavaScript in that jQuery library that the pages never use.