Difference between AJAX and jQuery

AJAX is a JAVASCRIPT TOOL whle JQUERY is a JAVASCRIPT LIBRARY.

AJAX is a denomination of several programming techniques. AJAX is not a specific technology but a combination of varying technologies to provide a new functionality. AJAX is not a new programming language, but a new way to use existing standards.Whenever you request a new set of data from web site, it clears the whole page and loads the new one. AJAX is used to circumvent this behavior and allow new data to be retrieved without modifying the whole page.

Examples of applications using AJAX: Google Maps, Gmail, Youtube, and Facebook tabs.

jQuery is a javascript framework that makes working with the DOM easier by building lots of high level functionality that can be used to search and interact with the DOM. By using we can make Ajax calls.

jQuery is a lightweight javascript library that ease the writting of javascript by levelling the differences between browsers and giving a common, simplified syntax. jQuery performs some commonly desired things so that author's don't need to reinvent some common wheels. jQuery focuses more on interactions with HTML elements. jQuery simplifies HTML document traversing, event handling, animating, and AJAX interactions for rapid web development. jQuery Libraries can be downloaded jquery.com.

jQuery handles Front End tasks while AJAX handles backend (server calls)

jQuery does all the work on the front end, therefore you would need to have a full understanding of it in order to properly set-up your page. You would not need to learn the exact mechanisms of AJAX in order to utilize it as jQuery gives you an AJAX command to retrieve whichever data you need from the server.

AJAX and jQuery are often used together

AJAX can’t be utilized with simple HTML since HTML doesn’t allow the page to be changed after it has fully loaded. In order to use AJAX, you would need a client side scripting language that allows you to detect the actions of the user and modify elements on the page accordingly. jQuery does that exactly, that is why both are often used together to present web pages that a user can interact with easily without repetitive loading.

Problem with AJAX and jQuery

Although the use of jQuery and AJAX makes the browsing experience a lot better for the user, the effect to the server hosting these files are not as desirable. Every time you make another AJAX request, a new connection to the server is made. Too many connections can sometimes be difficult for the server to cope with. Most hosting companies have made steps in order to prevent overloads since jQuery and AJAX are truly here to stay.

Summary:

1. jQuery is a lightweight client side scripting library while AJAX is a combination of technologies used to provide asynchronous data transfer.
2. jQuery and AJAX are often used in conjunction with each other.
3. jQuery is primarily used to modify data on the screen dynamically and it uses AJAX to retrieve data that it needs without changing the current state of the displayed page.
4. Heavy usage of AJAX functions often cause server overload due to the greater number of connections made.