HTTP Header Groups

All headers are divided into four main groups: general headers/d⁆, request headers/d⁆, response headers/d⁆, entity headers/d⁆.

General headers

General headers apply to both requests and responses, but have no bearing on the data carried in the body.

Request headers

Request headers contain more information about the resource to be retrieved or about the client requesting the resource.

Response headers

Response headers contain additional information about the response, such as its location or the server that provided it.

Entity headers

Entity headers contain information about the resource body, such as its content length or type. These include the Content-Type and Content-Length headers.