An HTTP response header is a component of a network packet that is sent by a Web server to a Web browser or client machine in response to an HTTP request. It is used in Web communications to deliver webpage and other Web-based data from the server to the requesting end-user browsers.
An HTTP response header primarily enables communicating and responding to user requests received on a Web server or the website. An HTTP response header works when a webpage or HTTP request is generated from the client’s Web browser. This request is received in the form of an HTTP request header to the Web server containing the source address, requested data and its format and other data. The Web server responds back by creating an HTTP response header and attaching the requested data with it. The information embedded with the HTTP response header includes the destination IP address, data type, host address and more.