HyperText Transfer Protocol (HTTP)

HyperText Transfer Protocol (HTTP) 

The HyperText Transfer Protocol (HTTP) is an Application layer protocol of ISO OSI Reference model. HyperText Transfer Protocol is very important protocol for World Wide Web.

HTTP was developed by Tim Berners-Lee at CERN (French: Organisation européenne pour la recherche nucléaire or in English European Organization for Nuclear Research) in 1989. The first version of HTTP came in 1997.

HTTP works as request-response protocol in client-server architecture. A web browser may be the client and an application program running on website hosting machine may be the server. The client submits an request message to the server machine. The server returns a response message to the client and provides resources such as web page, audio, video and performs other functions on the basis of client request.

A browser is an example of a user agent (UA) program. Some other user agent programs are indexing programs, mobile apps, voice browsers, and many more which provides the facility to accesses and displays web contents by the help of HTTP protocol.

HTTP defines methods/functions to perform the desired actions on web resources. Some methods of HTTP protocol are listed below:

GET: The GET method request represents a specified resource. This type of request retrieves only Data.

POST: The POST method sends request into encrypted form. It is more secure than the Get method.

HEAD: This method is useful for retrieving meta-data written in response header, without transporting entire content/matter.

DELETE: This method deletes the identified web resources.

TRACE: This method prints the received request so that the client can see the changes made by intermediate machine (servers).

OPTIONS: This method is used to examine the functionality of a web server machine.