How asynchronous is AJAX

In AJAX we use Asynchronous communication request/response model.decoupling user interaction from server interaction. As a result, the user can continue to use the application while the client program requests information from the server in the background. When new information arrives, only the related user interface portion is updated.And this is a big important point in the benfits

Exactly the process is like this only.
Due to this process user get information from the server...
Without undergoing of complete reloading of a page...

Asynchronous means that the script will send a request to the server, and continue its execution without waiting for the reply.

Yes, Ajax assists the web pages to update asynchronous by replacing same data with the server. The main feature is without reloading the whole page.

Good examples here:

ajax/sending-a-post-request-using-ajax-t598.html
ajax/my-first-ajax-application-t597.html
ajax/login-using-ajax-t3234.html