I absolutely despise the acronym "AJAX". Something about it rubs me the wrong way.
Perhaps it's a silly hang-up. Perhaps I'm foolish for not getting with the current lingo.
Nonetheless, I just don't feel comfortable with it. Not only is it impossible for me to say or write it with a straight face, I find it difficult to hear it from others without unconsciously stereotyping the other party as some sort of malleable, misinformed Johnny Come Lately.
It just seems like an uninformed way of uselessly simplifying a complex ecosystem of evolving and varying solutions into a meaningless, trite acronym (don't get me started on "Web 2.0").
Of course AJAX isn't really an acronym for anything anymore - realizing that it was founded on a solid foundation of ignorance, along with an unhealthy lack of historical knowledge, it has become a more generalized term meaning some sort of nebulous "interactive web application" (what we historically called a rich web application, or even the logically descriptive Dynamic HTML or DHTML). Now it's popular for it to just be the non-acronym "Ajax", with a much less restrictive meaning. If it's a cool web application, well that's courtesy of the new-fangled Ajax!
Even ridiculously pedestrian uses of scripted objects are hopping on the AJAX bandwagon these days. "It uses JavaScript...and that's the J....so it's AJAX!"
As a bit of "AJAX" history, way back in 1999 the Microsoft MSXML team - these were the people who made the superlative XML parser - added an oddball little object into the MSXML library: The XMLHTTP COM object. This object - one which originally used its own HTTP transport outside of IE's, leading to all sorts of proxy configuration fun - allowed one to programmatically send parameterized GET and POST requests to HTTP servers, retrieving data back for processing or display. They deserve credit for inventing it, but at the same time it was one of those inevitable solutions (in fact there were already safe for scripting third party HTTP clients, but of course they had very limited deployment).
XMLHTTP, like the rest of the MSXML COM library, was usable and valuable both by native applications, and by Internet Explorer client-side script (because they handily marked it as Safe For Scripting, which is the flag that reveals a COM component to the IE scripting engine). It isn't actually tied to XML in any meaningful way, and the XML misnomer was purely a result of it being created by the MSXML team (it was just a bit of namespace). Microsoft widely distributed the library alongside other products.
Voila, another method of background data loading was released to the world, adding to the already existing and utilized hidden-IFRAME technique. Like many developers in the Microsoft world, I saw the benefits of this relatively small enhancement, and started enabling internal web applications with partial page loading, rendering and post backs (using other parts of MSXML to transform received XML against an XSLT for display - a next generation technique that still has very limited deployment). Indeed, I even used this object in rich, native applications as an easy way of communicating with web services. It was a convenient little object.
All back in the year 2000, half a decade ago. I was hardly a pioneer, and there were thousands of others doing the same thing or more.
Nonetheless, given that it only worked with Internet Explorer, it was a complete non-starter for the public web, at least for the rational.
In early 2001, after seeing the value that it brought to the table, the Mozilla team added XMLHttpRequest to Mozilla 0.8. As the years passed, all of the other major-minor browsers incorporated compatible implementations. It was becoming a technology that was usable in the mainstream...but for one small issue: Up into even 2003, a lot of large corporations stuck with Netscape 4.x as their primary browser, or as their back-up cross-platform browser (e.g. they had Internet Explorer as their primary, with Netscape 4.x as the umbrella if Microsoft suddenly jacked up licensing costs and they needed to switch all of their client operating systems).
This lowest common denominator inhibited public sites, forcing them to stick with the tried and true, so even with the pervasive availability of this functionality across all of the late-model browsers it was still off-limits for widescale use because of a very small minority. Imagine a nation restricted by a 30km/h speed limits because there are a couple of people with old, beat-up Yugos, while everyone else is pounding their steering wheels in their beefed-up gas-guzzling 8-cylinders. That was the web world.
In late-2004/early-2005 Google shocked a lot of the blissfully-unaware world by adding XMLHttpRequest-backed functionality to Google Suggests, offering "type-ahead" usability enhancements (it can also use IFRAMEs, which is one of the original background-communication techniques). The moment was right, especially for a non-critical beta service, when the old (e.g. Netscape 4.7) could finally be tossed aside, and we could move ahead with technologies that have long been available. Google was the biggest player leading the way, but of course they weren't alone, and there were already plenty of public implementations of this sort of dynamic content that demanded a modern browser (Outlook Web Access, a component of Microsoft Exchange, being one of the earliest and best known).
Google Suggests was the largest, most visible implementation, and it opened a lot of web naysayers eyes up to what many of us had been evangelizing for years. Suddenly the unaware could see potential that had been there for years. Google also set a new bar for the amount of server side processing and bandwidth that could be allocated to a single random web visitor (not long ago it would have been considered insane to do that sort of processing and data transfer constantly as users typed keystrokes, for instance, but the availability of cheap computer cycles and copious bandwidth has changed the equation).
I'm going to segue to a little human-nature story here - I'm a Microsoft-centric user and developer: I chose to professionally focus on their tools and technologies as my specialty early on, and I've done very well with it (though I'll switch to other primary specialties if and when it's in my best interest). Nonetheless I regularly use Linux (primarily through the magic of virtual machines. I'd recommend that everyone does this, as an aside, especially now that VMWare has made their Player free. You owe it to yourself to give Linux a try - you will probably be surprized at how rich and capable it really is on the desktop), and I try to keep myself fairly competent with it. I have lots of experience with other OSs as well, though sadly I've yet to try OS X. Anyways, putting all of that operating system defensiveness aside, I've been with Windows for quite some time.
One thing I've noticed over the past several years, as a Windows user, is that quite a few historically anti-MSers are making the switch to (or back-to) Windows on their desktop. Perhaps Microsoft's security initiative is having an impact, or some other extenuating circumstance is making them want to switch, but nonetheless they're "coming back".
I feel that a lot of the AJAX hype follows the same pattern - someone either poo-poohed web applications for years, or perhaps their career just finally brought them to web applications. Instead of feeling that they're a junior in an established field, they have to invent some paradigm shift that renders everything that came before irrelevant.
Almost invariably they will defend their switch as being justified only by some relatively recent extraordinary revelation in the Windows platform - e.g. "That Windows 2000 was a real piece of crap, and I wouldn't have touched that with a 10-foot pole, but the new XP kernel is pretty good. Windows was crap before, but now it's good". Of course anyone who follows Windows knows that this is utter claptrap - XP is largely 2000 with a facelift and some relatively minor kernel changes. Really 2000 was already quite a well designed, nicely executed, very stable operating system, but they couldn't concede that prior iterations had value if they weren't a part of the game. Ultimately it only has value once they've entered the contest.
You can see this going the alternate direction as well - "Linux was garbage before kernel 2.x.x" - and for virtually any other technology. If someone is late to the game, there's a good chance that they'll try to manufacture some reason to validate making the switch now. Sometimes it's rational, but often it's just complete nonsense. I haven't spent any time with OS X, so instead I'll just wait a bit until the next iteration and declare whatever trivial change they've made to be the pivotal reason that justified my time.
This applies not only to engineers and their technologies, but to business hypsters as well - Instead of pimping themselves as yet-another entrant in the competitive web application market, they need to present the idea that they're coming at the perfect time: So much is possible now that wasn't possible yesterday.
I feel that a lot of the AJAX hype follows the same pattern - someone either poo-poohed web applications for years, or perhaps their career just finally brought them into web applications. Instead of feeling that they're a junior in a long established field, they have to invent or embrace some paradigm shift that renders everything that came before irrelevant. Disregard that the "technology stack" that facilitates a modern web application is extraordinarily wide and deep, and just pretend that this one small schism represents everything.
The crux of the matter, in my opinion, is that the acronym AJAX brings absolutely no clarity to the table, and instead introduces nothing but noise. Not only does it poorly define an implementation pattern that has been in use by experts for years, but its street use is so generic as to be detrimental (just look at that use of AJAX for the "AMASS" solution linked near the outset - Now AJAX just means "something done in a web app". How utterly inane). To others it is a buzzword that tries to simplify a multi-faceted technology platform into a nonsensically literal implementation detail, putting an inordinate amount of attention on one very small part of an interactive web application.
There is such a rich array of techniques and technologies available to a web developer to make a first rate platform, that such a simplistic and meaningless bit of language just confuses things.
Furthermore, there is this simpleton tendency for the hypsters and the unaware alike to see, or talk about, revolutions, where instead there has been a continual evolution (they're ignoring the fossil evidence!). One just has to read Tim O'Reilly's latest self-aggrandizement platform - Web 2.0 - to see this sort of distortion in action. Where many in-the-know see a constant evolution as the platform matured - everyone got faster computers, storage got cheaper, bandwidth became less expensive, the lowest common denominator got better, and so on - these people, with their enormous blind spot, instead see some monumentous divergence between yesterday and today. Yesterday was old-sk00l 1.0, and today is 2.0. Get it? Yesterday's car is a Model-T 1.0, and today's car is 2006 Honda Accord 2.0, with nothing in between.
Great, now come to my conferences, link my pages, and buy my not-open-source-but-open-source-is-great books!
http://www.yafla.com/