What partial content range types this server supports

Specifying which web sites can participate in cross-origin resource sharing

The age the object has been in a proxy cache in seconds

Valid actions for a specified resource. To be used for a 405 Method not allowed

Tells all caching mechanisms from server to client whether they may cache this object. It is measured in seconds

Options that are desired for the connection

An opportunity to raise a "File Download" dialogue box for a known MIME type with binary format or suggest a filename for dynamic content. Quotes are necessary with special characters.

The type of encoding used on the data. See HTTP compression.

The language the content is in

The length of the response body in octets (8-bit bytes)

An alternate location for the returned data

A Base64-encoded binary MD5 sum of the content of the response

Where in a full body message this partial message belongs

The MIME type of this content

The date and time that the message was sent (in "HTTP-date" format as defined by RFC 2616)

An identifier for a specific version of a resource, often a message digest

Gives the date/time after which the response is considered stale

The last modified date for the requested object

Used to express a typed relationship with another resource, where the relation type is defined by RFC 5988

Used in redirection, or when a new resource has been created.

This header is supposed to set P3P policy

Implementation-specific headers that may have various effects anywhere along the request-response chain.

Request authentication to access the proxy.

Used in redirection, or when a new resource has been created. This refresh redirects after 5 seconds.

If an entity is temporarily unavailable, this instructs the client to try again later. Value could be a specified period of time (in seconds) or a HTTP-date.[28]

The HTTP status of the response

A HSTS Policy informing the HTTP client how long to cache the HTTPS only policy and whether this applies to subdomains.

The Trailer general field value indicates that the given set of header fields is present in the trailer of a message encoded with chunked transfer-coding.

The form of encoding used to safely transfer the entity to the user. Currently defined methods are: chunked, compress, deflate, gzip, identity.

Tells downstream proxies how to match future request headers to decide whether the cached response can be used rather than requesting a fresh one from the origin server.

Informs the client of proxies through which the response was sent.

Indicates the authentication scheme that should be used to access the requested entity.

A general warning about possible problems with the entity body.