30.3. Ajax

The term Ajax—short for Asynchronous JavaScript and XML—was coined by Jesse James Garrett of Adaptive Path, Inc., in 2005 to describe a range of technologies for developing highly responsive, dynamic web applications. Ajax applications include Google Maps, Yahoo’s FlickR and many more. Ajax separates the user interaction portion of an application from its server interaction, enabling both to proceed in parallel. This enables Ajax web-based applications to perform at speeds approaching those of desktop applications, reducing or even eliminating the performance advantage that desktop applications have traditionally had over web-based applications. This has huge ramifications for the desktop applications industry—the applications platform of choice is shifting from the desktop to the web. Many people believe that the web—especially in the context of abundant open-source software, inexpensive computers and exploding Internet bandwidth—will create the next major growth phase for Internet companies.

Ajax makes asynchronous calls to the server to exchange small amounts of data with each call. Where normally the entire page would be submitted and reloaded with every user interaction on a web page, Ajax allows only the necessary portions of the page to reload, saving time and resources.