"In this tutorial I will give a short introduction to AJAX, lots of theory for the most part.

AJAX stands for Asynchronous JavaScript and XML and it actually a concept about transferring data between the browser and the server a-synchronically. So what a-synchronically means, is not that complicated to be honest to you - it is concept of exchanging information after the web page is loaded. Well normally, when you enter an URL in your browser and press enter the browser sends a GET request to server and asks for some data. And the server usually answers and lets the communications be established. During this communication your browser load data from the server and when it's done the connection interrupts."
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