Ajax

Several months ago, Jesse James Garnet of Adaptive Path coined the term Ajax as shorthand for Asynchronous JavaScript + XML. Ajax web applications take advantage of browser components to allow pages to be updated, not entirely refreshed. The net effect feels much more like a desktop application.

As mentioned in the Wikipedia entry, this is nothing new. The techniques have been in use since 1998. The first usage was a component for Outlook Web Access that became part of the MSIE 4.0 installation. Since then, plenty of web applications have used the approach and other browsers such as Firefox, Opera, Safari, etc. have added support for the XMLHTTP API that’s essential for building these applications.

So why is everyone suddenly talking about Ajax applications? Easy answer. Google. Google Maps, Google Suggest, Gmail, etc. use asynchronous communication to feel like “real” desktop apps, not constrained by the page-at-a-time nature of conventional web applications. I think the other reason is that a lot of people expect Ajax applications from Google and others to eventually replace desktop applications. For example, this ZDNet article lists several web-based Office suites, word processors, spreadsheets, etc. Clever stuff but I think its an extreme reach to suggest that these will replace desktop applications.

We’ve been down this path many times before. It’s great to have a “zero install” application but what about offline? And what happens when the server is down? Ajax is clever stuff but there are limitations. It will not be the appropriate approach for all applications.