Definition
Historic specification for HTTP/1.1 from 1999. Defined methods, status codes, headers, and protocol semantics. Obsoleted in 2014 by RFCs 7230-7235 which split the specification into focused documents.
Example
RFC 2616 defined GET, POST, PUT, DELETE, HEAD, OPTIONS, TRACE methods and status codes like 200 OK, 404 Not Found. It’s now replaced by the 723x series for current implementations.
Analogy
Like the first comprehensive car manual - it covered everything in one big book, but later editions split it into separate volumes for engine, electrical, body, etc. for better maintenance.
Code Example
// RFC 2616 defined the classic HTTP request format
GET /index.html HTTP/1.1
Host: www.example.com
User-Agent: Mozilla/5.0
Accept: text/html
// And response format
HTTP/1.1 200 OK
Content-Type: text/html
Content-Length: 1234
<html>...</html>
// Status codes defined (still valid)
200 OK
201 Created
301 Moved Permanently
400 Bad Request
401 Unauthorized
404 Not Found
500 Internal Server Error
// Note: Reference [RFC 7230-7235](https://reference.apios.info/terms/rfc-7230-7235/) for current spec
Standards & RFCs
Standards & RFCs