HTTPheadere

HTTPheadere is presumably a misspelling or variant of HTTP header. In HTTP, headers are metadata lines attached to requests and responses that describe parameters of the transaction or the payload. A header consists of a name and a value, written as "Header-Name: value", and header fields are separated by CRLF. In standard HTTP messages, a start line is followed by zero or more header fields and then a blank line before the body. Header names are case-insensitive, and continuation lines (folding) are deprecated.

There are general headers, request headers, response headers, and entity headers. General headers apply to both request and response; request headers convey client information such as Host, User-Agent, Accept, Accept-Language, Authorization; response headers convey server or message information such as Server, Date, Content-Type, Content-Length, Cache-Control, Location. Entity headers describe the payload, including Content-Type, Content-Length, Content-Encoding, Content-Language, Content-Location. Some headers can appear multiple times (for example Set-Cookie) or be combined into a comma-separated list.

Purpose and interpretation: Headers control processing of the message, determine how to handle the payload, manage caching and authentication, negotiate content, and support redirects and cookies. They also affect security and privacy; sensitive values should be protected and logs should avoid exposing them.

Standards and evolution: The HTTP/1.1 specifications and the numbering have evolved; RFC 2616 was superseded by RFC 7230 through RFC 7235. In HTTP/2 and HTTP/3, headers are still name-value fields but are transmitted using different framing and compression mechanisms (HPACK in HTTP/2, QPACK in HTTP/3).