AJAX has not only sprouted but has got root hold in developing dynamic web applications, that reflects changes in micro seconds thereby saving reloading time, improving usability, providing faster accessibility, to more web pages in lesser time. AJAX, acronym for Asynchronous Javascript And XML is the term whispered from almost every software developer mind and its waves are touching the network boundaries.

Ajax Applications Development has provided breakthrough in web application development. AJAX is a new way to define technology shifting web pages from HTML static pages to advance Java script and CSS enabled dynamic pages. AJAX is also called a free framework for fast creation of interactive cross-platform web experiences. This application has transformed the look, feel of web and has solved the major problem of web application of reloading.

Conglomeration of many technologies to form a more useful, dynamic, stronger technology - AJAX has accelerated the web world. Ajax incorporates standards-based presentation using XHTML and CSS; dynamic display and interaction using Document Object Model; data interaction and manipulation using XML; asynchronous data retrieval using XMLHttpRequest and Java Script binding together everything. AJAX uses Java script technology, HTML pages make asynchronous call to the server from which it fetches information that may be formatted as HTML, plain text, XML or Java Script Object Notation (JSON). To modify the Document Object Model (DOM) of the HTML page java script uses this content. Load of content on demand for various complex web applications has improved bandwidth usage by cutting down bandwidth consumption for complex functionalities.

AJAX is based on different server side architecture to support interaction model. Intermediate application layer, an Ajax engine (written in java script), is added in between user and server that allows asynchronous user’s interaction with application. This new approach has many benefits over static web applications, main features of AJAX include: Real-time form validation with server-side validation of codes. Auto-completion of form fields, better interaction and control with the use of advanced controls available. Content mix from third party application with your application is easily possible. Google Maps, Flickr, Orkut, Google Suggest are examples of AJAX application development.

Inspite of its myriad benefits, ajax application development is facing few major challenges: in-depth knowledge is required to understand upgrading Ajax functionality as it is not easy to develop Ajax that involves running complex java script code on client. Another challenge is that XMLHttpRequest object is not part of Java script technology specification, so it makes adaptablity difficult for older browsers. Even though browser add-ons have made debugging easy, processing logic embedded in client and on server makes application debugging difficult. Easy data access have provided easy way to plagiarism, except for restricted sections. Identifying particular state of application is difficult, this creates problem for user to bookmark specific application state. Also, iframe element used to populate browser history is not recommended by W3C. Websites using Ajax applications are generally not search engine friendly. Ajax has java script code that has compatibility problems with different browsers. Web analytics tracked records get cluttered with websites using Ajax technology as every event is tracked by analytics.

Careful consideration is required before implementing Ajax technology for your website to overcome few of its fallback.