Simply put, AJAX allows you to make a call to an http server (typically an RSS feed or a webpage), get it?
Each time you change the color, you will see the URL change, but still without a real postback/page reload, and you can now use your Back/Forward buttons in the brower.
With the addition of CSS and PHP, frames have become outdated, but if you wish to use them, read on.
Frames are most typically used to have a menu in one frame, and content in another frame.
This tutorial will be useful for web developers who want learn how to create interactive webpages as well as improve their speed and usability using AJAX.
It is highly recommended that you are familiar with HTML and Java Script before attempting this tutorial.