) is a set of web development
techniques using many web technologies on the client side
to create asynchronous web applications
. With Ajax, web applications can send and retrieve data from a server
asynchronously (in the background) without interfering with the display and behavior of the existing page. By decoupling the data interchange layer from the presentation layer, Ajax allows web pages and, by extension, web applications, to change content dynamically without the need to reload the entire page. In practice, modern implementations commonly utilize JSON
instead of XML.
Ajax is not a single technology, but rather a group of technologies. HTML