What is AJAX?
Conventional web applications transmit information to and from the server using synchronous requests. It means you fill out a form, hit submit, and get directed to a new page with new information from the server.
XML, JSON are commonly used as the format for receiving server data, although any format, including plain text, can be used.
AJAX is a web browser technology independent of web server software.
A user can continue to use the application while the client program requests information from the server in the background.
Intuitive and natural user interaction. Clicking is not required, mouse movement is a sufficient event trigger.
Data-driven as opposed to page-driven.
Using AJAX we can:
- Update a web page without reloading the page
- Request data from a server - after the page has loaded
- Receive data from a server - after the page has loaded
- Send data to a server - in the background
Who uses AJAX?
- Google Maps - A user can drag an entire map by using the mouse, rather than clicking on a button.
- Google Suggest - As you type, Google will offer suggestions. Use the arrow keys to navigate the results.
- Gmail - Gmail is a webmail, built on the idea that email can be more intuitive, efficient and useful.
- Yahoo Maps - These also use AJAX for interaction with the users.