Ajax isn’t a technology. It’s really several technologies, each flourishing in its own right, coming together in powerful new ways. Ajax incorporates:
old new twist being that one communicates with a server using Microsoft's proprietary XmlHttpRequest object. AJAX joins SOA in ignominy as yet another buzzword created by renaming existing technologies which becomes a way for some vendors to sell more products without doing anything new. I agree with Ian Hixie's rant Call an apple an apple where he wrote
Several years ago, HTTP was invented, and the Web came to be. HTTP was designed so that it could be used for several related tasks, including:
- Obtaining a representation of a resource from a remote host using that resource's identifier (GET requests).
- Executing a procedure call on a remote host using a structured set of arguments (POST requests).
- Uploading a resource to a remote host (PUT requests).
- Deleting a resource from a remote host (DELETE requests).
People used this for many years, and then suddenly XML-RPC and SOAP were invented. XML-RPC and SOAP are complicated ways of executing remote procedure calls on remote hosts using a structured set of arguments, all performed over HTTP.
Of course you'll notice HTTP can already do that on its own, it didn't need a new language. Other people noticed this too, but instead of saying "hey everyone, HTTP already does all this, just use HTTP", they said, "hey everyone, you should use REST!". REST is just a name that was coined for the kind of architecture on which HTTP is based, and, on the Web, simply refers to using HTTP requests.
Several years ago, Microsoft invented
The software industry perplexes me. One minute people are complaining about standards compliance in various websites and browsers but the next minute Google ships websites built on proprietary Microsoft APIs and it births a new buzzword. I doubt that even the fashion industry is this fickle and inconsistent.
Postscript: I wasn't motivated to post about this topic until I saw the comments to the post Outlook Web Access should be noted as AJAX pioneer by Robert Scoble. It seems some people felt that Outlook Web Access did not live up to the spirit of AJAX. Considering that the distinguishing characteristic of the AJAX buzzword is using XmlHttpRequest and Outlook Web Access is the reason it exists (the first version was written by the Exchange team) I find this highly disingenious. Others have pointed this out as well, such as Robert Sayre in his post Ever Wonder Why It's Called "XMLHTTPRequest"?