Define HTTP and briefly explain how operates.

HTTP, the Hypertext Transfer Protocol, is the application-level protocol that is used 

to transfer data on the Web. HTTP comprises the rules by which Web browsers and 

servers exchange information.

How Does HTTP Work? 

HTTP Is a request-response protocol. For example, a Web browser initiates a 

request to a server, typically by opening a TCP/IP connection. The request itself 

comprises 

o a request line, 

o a set of request headers, and 

o an entity. 

The server sends a response that comprises 

o a status line, 

o a set of response headers, and 

o an entity. 

The entity in the request or response can be thought of simply as the payload, 

which may be binary data. The other items are readable ASCII characters. When the 

response has been completed, either the browser or the server may terminate the 

TCP/IP connection, or the browser can send another request. 

Cheers!

Short for HyperText Transfer Protocol, HTTP is the underlyingprotocol used by the World Wide Web. HTTP defines how messages are formatted and transmitted, and what actions Web servers and browsers should take in response to various commands. For example, when you enter a URL in your browser, this actually sends an HTTP command to the Web server directing it to fetch and transmit the requested Web page.

The other main standard that controls how the World Wide Web works is HTML, which covers how Web pages are formatted and displayed.

HTTP is called a stateless protocol because each command is executed independently, without any knowledge of the commands that came before it. This is the main reason that it is difficult to implement Web sites that react intelligently to user input. This shortcoming of HTTP is being addressed in a number of new technologies, includingActiveX, Java, JavaScript and cookies.

http in simple word is a set of protocols or rules followed by web developers as well as the browser application developers. web page is developed in such a manner that its resources will be loaded on client side normaly in any browser which follows the universal hyper text terminal protocols regardless of the browser & according to the set of instructions provided by the webdeveloper.

Afsheen has explained very well. Here is another anwser:

Short for HyperText Transfer Protocol, HTTP is the underlying protocol used by the World Wide Web. HTTP defines how messages are formatted and transmitted, and what actions Web servers and browsers should take in response to various commands. For example, when you enter a URL in your browser, this actually sends an HTTP command to the Web server directing it to fetch and transmit the requested Web page.

The other main standard that controls how the World Wide Web works is HTML, which covers how Web pages are formatted and displayed.

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