AJAX Introduction

What is AJAX ?

AJAX is  Asynchronous JavaScript and XML. AJAX is a new technique for creating better, faster, and more interactive web applications with the help of XML, HTML, CSS and Java Script.

AJAX allows web pages to be updated asynchronously by exchanging small amounts of data with the server behind the scenes. This means that it is possible to update parts of a web page, without reloading the whole page.

The Conventional web application transmit information to and from the sever using synchronous requests. This means you fill out a form, hit submit, and get directed to a new page with new information from the server.

AJAX when submit is pressed, JavaScript will make a request to the server, interpret the results and update the current screen. So many applications are using  AJAX  they are following : Google, bing, yahoo, goole Maps, Gmail, Youtube, and Facebook tabs, linkedin etc.
ajax introduction
AJAX is Based on Internet Standards

AJAX is based on internet standards, and uses a combination of :

  • XMLHttpRequest object : To exchange data asynchronously with a server.
  • JavaScript/DOM : To display/interact with the information.
  • CSS : To style the data.
  • XML : Often used as the format for transferring data.
Google Suggest

AJAX was made popular in 2005 by Google, with Google Suggest.

Google Suggest is using AJAX to create a very dynamic web interface: When you start typing in Google's search box, a JavaScript sends the letters off to a server and the server returns a list of suggestions.