AJAX Introduction

AJAX is a technology that can update some pages without reloading the entire page.

Basic knowledge you should have

Before continuing, you need to have a basic understanding of the following knowledge:

  • CSS
  • JavaScript /DOM

If you want to learn these items first, please visit these tutorials on our Homepage .

What is AJAX?

AJAX = Asynchronous JavaScript and XML.

AJAX is a technology for creating fast and dynamic web pages.

AJAX enables web pages to be updated asynchronously with a small amount of data exchange with the server in the background. This means that parts of a web page can be updated without reloading the entire web page.

Traditional web pages (not using AJAX) need to reload the entire web page if content needs to be updated.

There are many examples of applications using AJAX: Sina Weibo, Google Maps, Kaixin.com, and more.

AJAX is based on existing Internet standards

AJAX is based on existing Internet standards and uses them in conjunction:

  • XMLHttpRequest object (asynchronously exchanges data with the server)
  • JavaScript /DOM (information display /interaction)
  • CSS (styling data)
  • XML (as a format for transforming data)

lamp  AJAX applications are browser and platform independent!

Google Suggest

In 2005, Google made AJAX popular with its Google Suggest.

Google Suggest uses AJAX to create a highly dynamic web interface: When you enter keywords in Google's search box, JavaScript sends these characters to the server, and the server returns a list of search suggestions.

Start using AJAX today

AJAX is based on existing standards. These standards have been used by most developers for many years.

Read the next chapter and see how AJAX works!