Ajax allows a developer to create pages that are updated asyncronously by sending and recieving small amounts of data through the server in the background. This means you can reload data on the page without actually reloading the page itself. Some examples of sites that use AJAX to create this type of features are Google Maps, Youtube and Facebook tabs. In fact the AJAX method was made popular in 2005 being used with Google Suggest.
How does AJAX work?
- Browser creates an XMLHttpRequest object and sends it
- Server processes the HTTPRequest, creates a response and sends the new data back to the browser