The term AJAX

Asynchronous JavaScript and XML, or Ajax is a web development technique for creating highly responsive and efficient Rich Internet Applications (RIA). This technique relies on a combination of several core technologies including DHTML, CSS, XML, JavaScript, and the XMLHttp Request Object. Modern browsers have all of these technologies enabled, thereby making Ajax a reliable tool for the creation of Rich Internet Applications.

AJAX Revolution

AJAX-based Rich Internet Applications deliver groundbreaking, highly interactive interfaces that provide the user with an experience similar and often superior to that of desktop applications. This opens up a wholly new realm of possibilities for customer-facing, B2B and Intranet applications.

In its May 2005 report, "Rich Internet Applications Are the Next Evolution of the Web", Gartner aired the following ideas and predictions regarding RIA:

• "A new application model is emerging that addresses the gap between the fat but rich client/server UI model and the thin but poor Web-based UI model".
• "By 2010, at least 60 percent of new application development projects will include RIA technology, and at least 25 percent of those will rely primarily on RIA".

Differences between standard web applications and AJAX-based Rich Internet Applications

The goal of AJAX is to improve user experience. With each action traditional web applications cause a page refresh, getting new content from the server-side script. From the user's point of view this is a time-consuming action that also removes the context of the user interface. To give an analogy from the desktop world, just imagine that the screen goes blank for a short while, the application completely closes and opens again showing a new screen when you press any button or choose something from the menu. What an annoyance, but this is exactly what happens with multi-page web applications.

AJAX innovation is a dynamic single-page user interface: instead of a complete refresh only the relevant parts of a page are updated. In addition, the AJAX user interface responds to individual user events (for example, key strokes or mouse movements). In contrast to traditional web applications, AJAX applications perform updates in the background so that the user can continue working while updates take place. The result of such innovations is a dynamic user interface that looks and feels like a desktop application.