Name
Host
Synopsis
The Host header is used by clients to provide the server with the Internet hostname and port number of the machine from which the client wants to make a request. The hostname and port are those from the URL the client was requesting.
The Host header allows servers to differentiate different relative URLs based on the hostname, giving the server the ability to host several different hostnames on the same machine (i.e., the same IP address).
Type
Request header
Notes
HTTP/1.1 clients must include a Host header in all requests. All HTTP/1.1 servers must respond with the 400 Bad Request status code to HTTP/1.1 clients that do not provide a Host header.
Basic Syntax
Host: host [”:" port]
Example
Host: www.hotbot.com:80
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