An asynchronous JavaScript and XML is called AJAX. It acts always not exactly in the presence of the code. In order to get a response from a webpage or any web services, it calls the methods.

Below are a few advantages of Ajax.

• The main advantage is Ajax helps to reduce traffic which happens between the client and server.
• The speed and performance are more because of its fast response time.
• Firefox browsers generally use Ajax with Firebug to debug all the asynchronous errors.
• The HTTP protocol is used to communicate which is user-friendly.

Which is better?

Advantages of Ajax

• Improved User Experience: One of the main advantages of AJAX is enhanced user experience. It is easy to update the webpages by just interchanging a little amount of data with the server. With the help of this, you can easily update the parts of the webpages without reloading the page. It is very helpful in comparison with the other classic webpages where reloading is a must.
• Better Infrastructure:We are living in the modern world where most of the homes have broadband and server capacities. AJAX application can be hungry for both server capacity and bandwidth due to the frequent back-and-forth between client and server.

Atlas

• There is a framework named Atlas which is an older form of Microsoft AJAX library which integrates the Client-side JavaScript library. It is easily available which is used with ASP.NET to develop AJAX applications. It uses cross-browser and exposes object-oriented APIs which is very helpful in developing web applications that not only reduce the network load/server hit but also perform asynchronous processing.
• Increasing Productivity: There are many functions in the AJAX library that can increase overall productivity without getting frustrated. The well configured ASP.NET application has its own data access along with the business layer. Moreover, it also comprises of the UI layer where the server-side operations are performed.
• Form validation:AJAX provides the validation of forms which is the biggest advantage. As, we know, forms are the important elements in the web pages, so instant validation improves the speed as well as security.
• Speed: AJAX reduces the traffic that travels between the client and the server-side request and the response. This lead to fasten the response time, which increases the performance and speed.

Disadvantages of AJAX:

• Browser Incompatibility: AJAX is highly dependent on the JavaScript which is executed separately for various browser. So, where AJAX has to work across multiple browsers it creates the problems. The browsers which do not support or which select disable for the JavaScript are not able to work properly. As it is so dependable it is not good to design the mobile applications.
• Performance Concerns: Regular interaction between the browser and the server makes the application less responsive. Although there are some solutions to it like browser-side caching. These tricks work, even for active applications like stock trading but it might not work for time-critical applications like machine control.
• Not Search Engine Friendly: Another major key problem of the AJAX is that it is not good for the search engines because the dynamically rendered content is not noticeable to the search engine. Therefore, AJAX-driven pages are not likely to rank great in the search rankings.
• Second Programming Language: If you are desired to work in the AJAX application you must have the basic knowledge of the JavaScript. Most of the developers are find that JavaScript is more proficient language, but there is however an imposition to utilize a language different to that on the server-side.