Javascript or Ajax

[ceejay77]

I have seen the word Ajax mentioned before is it a replacement to Javascript or a add on is it worth the change,what are the benefits?

[DavidAllen]

Neither actually
AJAX (Asynchronous Javascript And XML) uses javascript to communicate with the server and enables it to update just part of a webpage.
Benefits are that the user gets a much more 'interactive' experience and because you are not reloading the whole page it is a lot quicker.
The ascynchronous bit means it goes on in the background and doesn't 'freeze' up the page whilst waiting for its data.

See wikipedia for more information

[GalaxyMan]

David is correct, I'd recommend learning it (AJAX) as it's quite popular nowadays especially if you're creating a 2.0 web service. I've seen several URL shrinking sites as well as image hosts implement it.

[VPWhat]

I would say that AJAX is going to have a big part in the future of web design. Just to give you an example of the kind of thing that can be done with it, Facebook is coded in AJAX. Very powerful tool.