Ajax

What is it?

Jesse James Garrett

The name is shorthand for Asynchronous JavaScript + XML, and it represents a fundamental shift in what's possible on the Web.

Ajax isn't a technology. It's really several technologies, each flourishing in its own right, coming together in powerful new ways.

Ajax: A New Approach to Web Applications

Derek Powazek

If the traditional web was letter writing, Ajax is instant messaging.

Me

Ajax is a way of communicating with the server without refreshing the whole page.

Examples

• Flash (Flex)
• Frames
• Java applets
• Hidden iFrame
• XMLHttpRequest

So what?

You can update part of a document instead of refreshing the whole thing.

What's the big deal?

Wow!

You can update part of a document instead of refreshing the whole thing!

Holy crap!

More than DOM Scripting

Communication with the server is what distinguishes Ajax from DOM Scripting/DHTML

The Ajax toolkit

• (X)HTML
• Any server-side language
• XML… maybe
• JavaScript
• The Document Object Model
• XMLHttpRequest