To summarize what has been discussed so far, I would like to highlight some of the important aspects of the client-to-server communication. Communications based on a system of special rules and formats for messages to enable data exchange between clients and servers is known as a communication protocol. Any device connected to the Internet has a unique IP address. A message transmitted from one device to other over the Internet follows a long route to be delivered via the protocol stack. HTTP is a text-based application protocol that makes the Web work. Web browsers or standalone applications send a request and open a connection to the web server. The web server complies with the request and closes the connection to the web client.

AJAX is a technology that allows client-side JavaScript code to request data from a server without reloading the current page in the web browser. HttpRequest (formerly XMLHttpRequest) has an important role in the AJAX web development technique. The AJAX...