An HTTP request header primarily enables a user in accessing a website. Each time a user website or webpage in a browser, an HTTP request header is generated by the browser and is sent to the website / Web server. Typically, the information within the HTTP request header is in form of plain text record of data/page request made by the user. Some of the information within an HTTP request header includes:

• Source IP address and port number

• Requested URI (data or web page)

• Host (Destination website or web server)

• Type of data the browser will accept in return (text, html, xml etc)

• User’s browser type (Mozilla, Chrome, IE) so that the Web server can send compatible data

In response, the Web server/host sends back an HTTP response header containing the requested data.