To develop a webpage multiple languages are being used in these days. Once in early, there was only HTML language was used to develop a webpage but history changed, technologies were changed. Many things related to developing web pages came to existence like the concept of Server Side Languages, Client Side Languages etc.

You might been noticed that some of web page developmental languages derived from other languages and some were combined to produced one single language containing the features of many languages in one.

Same thing applies here with JQuery (a lightweight JavaScript Library is used for interaction between JavaScript and HTM) and AJAX (Asynchronous JavaScript and XML creates a group inter-related methods use in web development. These methods further use to build interactive website applications. These methods are used on client side.).

As result, you seen above, JQuery is derived from JavaScript and AJAX is a combination of multiple technologies. All technologies use in AJAX provides one purpose only to send request from client side to server to perform a set of operations. There are some constraints by HTML, once page fully loaded HTML does not allow changing its contents. Furthermore, HTML also does not permit to use AJAX simply. To use AJAX you need to use some client side scripting language, this client side scripting language detects actions requested by end users and alters elements page accordingly to client side webpage. JQuery also performs same things. For this reason, both jQuery and AJAX are used together. This combination of JQuery and AJAX provides end user to get rid off from frequently full page loading, allows to end users to interact with web pages easily.

AJAX:

In Ajax, it combines HTML, XHTML and CSS to produce presentation of webpage. DOM (Document Object Model) is used display dynamically and makes it possible to interact with data. XML is responsible for interchanging of data. XSLT is used for its manipulation. For asynchronous communication the XMLHttpRequest is used and JavaScript brings all these technologies into a bunch.

Drawbacks of AJAX:

• AJAX enables web pages do not store its items into history of web browsers. Once it loads, you want to go previous state of webpage and you press web browser’s back button, you see there is no earlier state of webpage.
• It is difficult to bookmark current state of webpage, since it does not store history of web browser. You may loss content next time your book marked webpage on opening.
• Requires fast internet speed to perform actions rapidly
• If your browsers do not support JavaScript, AJAX will not run. Generally, mobile phone web browsers, PDA and screen readers do not have JavaScript web browsers, so AJAX restricts area of accessibility of webpage among all users.
• Mostly, web crawlers do not execute JavaScript, so search engines do indexing JavaScript less contents of webpage.

JQuery:

• JQuery is being used in 31% of 10,000 websites.
• It is mostly popular JavaScript Library today.
• It is open source cross browser.
• JQuery uses DOM elements. Easy to implement
• CSS manipulation
• Elegant effects and animations
• Plug-ins are used for extendibility
• Cross browsers supports
• Accessibility in Mobile Web Browsers, PDAs etc.