Ajax Callback

Ajax call back works like this:

1-The browser send a message (i.e data) to the server and specifies the page on the server that will receive the messagge.

2-The browser does not wait until a response is received from the server, the user is not prevent from doing something else during the ajax callback.

3-The message from the browser is received and the page that was specified in the ajax ca;llback runs.