What is Ajax Programming? Category:Ajax Programming Published 12/29/2007 10:57:53 AM by Mark Brooke
Ajax, or AJAX, is a web development technique used for creating interactive web applications. The intent is to make web pages feel more responsive by exchanging small amounts of data with the server behind the scenes, so that the entire web page does not have to be reloaded each time the user requests a change. This is intended to increase the web page's interactivity, speed, functionality, and usability.
The name is shorthand for Asynchronous JavaScript and XML. Ajax is asynchronous in that loading does not interfere with normal page loading. JavaScript is the programming language in which Ajax function calls are made. Data retrieved using the technique is commonly formatted using XML, as reflected in the naming of the XMLHttpRequest object from which Ajax is derived.
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 XML, together with open source implementations of other required technologies.
The core justification for Ajax style programming is to overcome the page loading requirements of HTML/HTTP-mediated web pages. Ajax creates the necessary initial conditions for the evolution of complex, intuitive, dynamic, data-centric user interfaces in web pages—the realization of that goal is still a work in progress.
Web pages, unlike native applications, are loosely coupled, meaning that the data they display are not tightly bound to data sources and must be first marshaled (set out in proper order) into an HTML page format before they can be presented to a user agent on the client machine. For this reason, web pages have to be re-loaded each time a user needs to view different datasets. By using the XMLHttpRequest object to request and return data without a re-load, a programmer by-passes this requirement and makes the loosely coupled web page behave much like a tightly coupled application, but with a more variable lag time for the data to pass through a longer "wire" to the remote web browser.
Ajax programming is available within all Bayley/Brooke web development projects.
