Asynchronous JavaScript and XML (AJAX) is a development technique used to create interactive web applications or rich internet applications. AJAX uses a number of existing technologies together, including: XHTML, CSS, JavaScript, Document Object Model, XML, XSLT, and the XMLHttpRequest object.
With AJAX, web applications can retrieve data from the server asynchronously, in the background, without reloading the entire browser page. The use of AJAX has led to an increase in interactive animation on web pages.
Advantages
- Reduces the traffic travels between the client and the server.
- No cross browser pain.
- Better interactivity and responsiveness.
- With AJAX, several multi purpose applications and features can be handled using a single web page(SPA).
- API’s are good because those work with HTTP method and JavaScrtipt.
Disadvantages
- Search engines like Google would not be able to index an AJAX application.
- It is totally built-in JavaScript code. If any user disables JS in the browser, it won’t work.
- The server information can not be accessed within AJAX.
- Security is less in AJAX applications as all the files are downloaded at client side.
- The data of all requests is URL-encoded, which increases the size of the request.
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