AJAX

What is AJAX software Programming?

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 Java Script.
  • It uses XHTML for content, CSS for presentation, along with Document Object Model and JavaScript for dynamic content display.
  • Conventional web applications transmit information to and from the sever 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.
    • smitted to the server.
  • XML is commonly used as the format for receiving server data, although any format, including plain text, can be used.
  • It 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.

AJAX is Based on Open Standards

  • Browser-based presentation using HTML and Cascading Style Sheets (CSS).
  • Data is stored in XML format and fetched from the server. Behind-the-scenes data fetches
  • using XMLHttpRequest objects in the browser.
  • JavaScript to make everything happen

How Does AJAX Work?

JavaScript and XML combine to make asynchronous updating happen through the use of something called an XMLHttpRequest object. When a user visits a web page designed to make use of AJAX and a prescribed event occurs (the user loads the page, clicks a button, fills out a form, etc.)

JavaScript creates an XMLHttpRequest object, which then transfers data in an XML format between a web browser (the program being used to view the website) and a web server (the software or hardware where a website’s data is stored).

The XMLHttpRequest object sends a request for updated page data to the web server, the server process the request, a response is created server-side and sent back to the browser, which then uses JavaScript to process the response and display it on the screen as updated content.

To recap: JavaScript automates the updating process, the request for updated content is formatted in XML to make it universally understandable, and JavaScript again kicks in to refresh the relevant content for the user viewing the page.

Cascarano notes that the AJAX technique ignores extraneous page data and only handles requests for updated information and the updated information itself. This is really the heart of AJAX’s effectiveness, making websites and applications that use AJAX faster and more responsive for users.