Ajax is undoubtedly a revolutionary web technology. It helps the web developers design and implement rich and interactive websites.

Ajax is not a technology in itself, but a group of technologies. Ajax uses a combination of:

• HTML and CSS for webpage content and styles.
• The DOM accessed with JavaScript to dynamically display and interact with the information presented.
• A method for exchanging data asynchronously between browser and server, thereby avoiding page reloads (page refresh). The XMLHttpRequest (XHR) object is usually used, but sometimes an IFrame object or a dynamically added <script> tag is used instead.
• A format for the data sent to the browser. Common formats include XML, pre-formatted HTML, plain text, and JavaScript Object Notation (JSON). This data could be created dynamically by some form of server-side scripting.

We have been using Ajax since 2006, when it was still a new technology. We have implemented Ajax on several of our websites, making them richer and more interactive. We have been using Ajax tools such as ASP.NET Ajax and Ajax Control Toolkit. We have also developed our own Ajax utilities for our web projects, as and when required.

We use Ajax in both ASP.NET and PHP developments. While built-in tools make it easy to implement Ajax in ASP.NET, we have used our own tools to implement it in PHP websites.