AJAX (Asynchronous JavaScript and XML), is a web development technique used for creating interactive web applications. AJAX is asynchronous in that extra data is requested from the server and loaded in the background without interfering with the display and behaviour of the existing page.

JavaScript is the scripting language in which AJAX function calls are usually made.

AJAX is a cross-platform technique usable on many different operating systems, computer architectures, and web browsers as it is based on open standards such as JavaScript and the DOM.