This page provides a listing of HTTP entity headers and what they are used for. Entity headers:
ALLOW - Lists the set of methods ( for the web browser) supported by the resource(web server) identified by the Request-URI.. It lists the request methods (GET, POST, etc) allowed by the server for the client.
CONTENT-ENCODING - This header describes the content encoding the returned document is formatted in. An example is:
CONTENT-LANGUAGE - Describes the natural language for the document ot be returned to the client web browser.
CONTENT-LENGTH - The size of the document being returned in decimal number of OCTETs (bytes).
CONTENT-LOCATION - The Content-Location entity-header field MAY be used to supply the resource location for the entity enclosed in the message when that entity is accessible from a location separate from the requested resource's URI.
Content-MD5 - An MD5 digest of the entity-body for the purpose of providing an end-to-end message integrity check (MIC) of the entity-body. (Note: a MIC is good for detecting accidental modification of the entity-body in transit, but is not proof against malicious attacks.)
CONTENT-TYPE - Iindicates the media type of the entity-body sent to the recipient or, in the case of the HEAD method, the media type that would have been sent had the request been a GET. In short, it tells the web browser What MIME type the document is that is being sent to it. An example:
Content-Type: text/html; charset=ISO-8859-4
CONTENT-RANGE - Sent with a partial entity-body to specify where in the full entity-body the partial body should be applied.
DATE - Represents the date and time at which the message was originated.
EXPIRES - The date/time after which the response is considered stale.
LAST-MODIFIED - Indicates the date and time at which the origin server believes the variant (document being sent to the browser) was last modified.