What is Ajax?

Until recently there wasn't any way of having Javascript update web pages with any information not downloaded as part of the page

If you have been hiding under a rock or in a cave or some other out of the way place then you may have missed all of the hype of the last year or so and be wondering Just what Ajax actually is. Well Ajax is just a new "cool" term for an existing method of sending requests back to the server so as to update the existing page with new information without having to reload the whole page. This series of tutorials will introduce you to the basic concepts.