AJAX

AJAX is a new name coined by Jesse James Garrett of Adaptive Path for two old technologies: JavaScript and XML. Basically, AJAX applications asynchronously connect to the server to collect more data that can be displayed in the current Web page. As a result, new information can be shown without page refresh. Google was the first to popularize this strategy with their Gmail and Google Maps applications. However, Google was not the first to make full use of the engine that makes asynchronous connections possible: the XMLHttpRequest object. Microsoft added it to Internet Explorer 5 and seasoned developers discovered ways to reap its benefits. Soon afterwards Mozilla browsers also had their own version of this object. Prior to XMLHttpRequest, people used DHTML and HTML frames and iframes to update pages without refresh.

Despite advance in client-side technologies, writing JavaScript code, hence AJAX applications, is still intimidating. Even though IDEs are available for writing JavaScript scripts, programmers still have to overcome the biggest challenge in writing client-side applications: browser compatibility. It is a fact of life that every browser implements JavaScript slightly differently from each other. Even the same browser does not interpret JavaScript in the same way in different operating systems. As a result, you have to test your script in various operating systems using various browsers and write multiple versions of code that work in all browsers.

This is where OpenLaszlo comes to rescue. With OpenLaszlo, you only need to write and test once and let it worry about browser compatibility. Needless to say, using OpenLaszlo as your AJAX platform saves an awful lot of time. Support for AJAX started since OpenLaszlo 4.0 (code-named Legals). Prior to this release, OpenLaszlo could only generate Flash. Now you can choose between AJAX and Flash.