Apache 2 Pocket Reference

Appendix E. HTTP Header Fields

HTTP header fields are defined in RFC 2616 and summarized in Table E-1. They may be categorized as:

Request Header Fields

Contain additional information about the request

Response Header Fields

Contain additional information about the response

General Header Fields

Applicable to both request and response messages

Entity Header Fields

Contain information about the entity body or the resource identified by the request

Table E-1. HTTP headers

Syntax	Category
Accept: media-types[;q=qvalue][, ...]	Request
Accept-Charset: charset[;q=qval][, ...]	Request
Accept-Encoding: enc[;q=qvalue][, ...]	Request
Accept-Language: lang[;q=qvalue][, ...]	Request
Accept-Ranges: [bytes | none ]	Response
Age: seconds	Response
Allow: method[, ...]	Entity
Authorization: scheme credentials	Request
Cache-Control: directive	General
Connection: close	General
Content-Base: uri	Entity
Content-Encoding: enc	Entity
Content-Language: lang	Entity
Content-Length: len	Entity
Content-MD5: digest	Entity
Content-Range: bytes range/length	Entity
Content-Type: media-type	Entity
Cookie: name=value[; ...]	Request
Date: date	General
ETag: entity-tag	Response
Expect: expectation	Request
Expires: date	Entity
From: email-address	Request
Host: hostname[:port]	Request
If-Match: entity-tag	Request
If-Modified-Since: date	Request
If-None-Match: entity-tag	Request
If-Range: { entity tag | date }	Request
If-Unmodified-Since: date	Request
Last-Modified: date	Entity
Location: uri	Response
MIME-Version: version	General
Max-Forwards: number	Request
Pragma: { no-cache | extension-pragma ...