Glossary:
AJAX
AJAX is shorthand for asynchronous JavaScript and XML.
It is a technique of using client-side JavaScript and server-side XML data to create interactive web applications that appear to work like desktop applications without the need to reload an entire web page.
Web applications can be coded to retrieve data from the server asynchronously so that the web browser interface continues to work while data is loaded in the background.
Potential problems with Ajax occur when a web browser does not support Ajax or JavaScript, or simply has JavaScript disabled. The browser will not be able to use the dynamic functionality. Similarly, devices such as mobile phones, PDAs, and screen readers may not have support for JavaScript.