New uses of Ajax are constantly being discovered and old uses are still being refined. This page provides an overview of some of the most general purposes for Ajax, as well an interesting new use or two.
The most obvious use of Ajax is to create a new rich Internet application. Rich Internet applications (RIAs) are Web applications that deliver the same features and functions normally associated with desktop applications. RIAs typically run inside a Web browser and do not require the user to download or install any software on their end.
Another common use of Ajax is to create an enterprise mashup. Enterprise mashups allow users to combine data and applications from disparate sources into new services. Our Enterprise Mashups Tutorial provides definitions, tips, examples and strategies you can use to better understand and implement enterprise mashups.
A more complicated use of Ajax is reverse Ajax (or Comet). Reverse Ajax is a way of updating the client as needed from the server side, without interrupting or refreshing the browser. In order to understand why one would need something like Comet, one need just look at the nature of real-time events, such as those occurring in the stock market or in sporting matches. These are situations where data will sometimes urgently need to be updated with high frequency and can sometimes remain static for long periods of time.
The Facebook website's innovative use of open APIs has an influence in Web application design. Facebook replaced its Facebook Connection API with an interface that will allow any page on the Internet to be managed like a Facebook fan page. This change promises to make it easier for more applications to collect and manage data in the Facebook social graph. In effect, this change will allow developers to use Facebook's Open Graph API to program the Web.
If you found this page interesting you may want to read more from our Ajax tutorial.