Advantages and Disadvantages
The major advantage to developing an application using this technique is that there are very few browsers for which this method does not work, including older browsers. In fact, the only thing that some web developers might consider out of the ordinary is the use of hidden frames. Nevertheless, it works, which is all that really matters when developing an application.
Unfortunately, problems begin to arise when an inexperienced developer attempts to maintain an application developed using this technique. In fact, several years ago, I developed an application that used hidden frames for an insurance company. It was one of the few applications for which I received calls after leaving the company. It was explained to me that there wasn't anything wrong with the applicationin fact, it worked wonderfullybut the new developers couldn't quite grasp how it worked. To the new developers, the application was a classic black box; information went in and information came out, but what happened to it in the box was a complete mystery.
The final problem with this technique is that it really isn't Ajax; it only offers a similar look and feel. Think of it as a kind of primitive ancestor to Ajax or, if you prefer, as flexing our mental muscles getting ready for the main event. So now that we're all warmed up, let's push the knuckle-walking ancestor out the door and move on to the next chapter and something that everybody will agree is Ajax.