Is Ajax purely for an enhanced experience?

Question

Aside from enhanced user experience, do Ajax calls provide any significant performance benefit?

Answer 1

Before even Ajax was coined, then popularized, programmers go to great lengths(using the combination of javascript and inner frame) to make their web app responsive and provide enhanced user experience.

It also provides significant performance, instead of re-rendering the page, your ajax web app only communicate with the server to get data and update only some parts of screen accordingly.

The first A(Asynchronous) in AJAX, also tells it all, as long as your web app facilitates asynchronous operations(think autocomplete), your web app is already way ahead in terms of enhanced user experience, user-friendliness. Though not all programmers uses the first A(some just make things synchronous to simplify the code).

For all intents and purposes, AJAX makes for great user experience, the Ask Question of Stack Overflow is one good example, using AJAX, it can preemptively prevent duplicate post.

Answer 2

In this case it's the same thing.

The user's experience is enhanced because there are performance benefits.

1) The web browser doesn't need to repaint the entire page. Firefox 3 has made improvements with this but:

2) The user perceives your web application to be faster and therefore, for all intents and purposes, it is.

I use Ajax whenever it makes sense and I can because the flow and feel of the web application is just smoother.

Answer 3

whether you gain performance depends on how your "ajax" was implemented. I say it wouldn't be faster (at least for the serverside) if you just push markup straight from the server to the client without the client doing much processing.

Answer 4

As a wanted side-effect to enhanced experience (only what's needed is refreshed), there's less strain on and to the server. This means, the service provider manages with less hardware, and also a smaller bill for the Internet connection (less bits are transferred over the wire).

Of course, some might argue, the main and side effects should be the other way around.