< Ajax Tutorial

Ajax introduction

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What is AJAX?

  • AJAX stands for 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 JavaScript.

  • Ajax uses XHTML for content, CSS for presentation, along with Document Object Model (DOM) and JavaScript for dynamic content display.

  • 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.

  • With AJAX, when you hit submit, JavaScript will make a request to the server, interpret the results, and update the current screen. In the purest sense, the user would never know that anything was even transmitted to 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.
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