Does ajax require a web service?

Question

If I want to get data to update partially in a page with jquery (or something else) ajax, does the page I call have to be a web service? Or will just any page that returns json or xml be fine?

I guess I'm asking it like this because in asp.net you have "offical" web services. In other languages and frameworks they may not be like that. I know for example that I can create a classic asp page and return an xml document. Is that a web service?

Answer 1

It doesn't even have to return JSON or XML--it can return HTML or text that you can just drop into the calling page.

I've used "all of the above" in one place or another.