Internet Engineering Task Force (IETF)                  R. Fielding, Ed.
Request for Comments: 7231                                         Adobe
Obsoletes: 2616                                          J. Reschke, Ed.
Updates: 2817                                                 greenbytes
Category: Standards Track                                      June 2014
ISSN: 2070-1721


        Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content

Abstract

    The Hypertext Transfer Protocol (HTTP) is a stateless application-
    level protocol for distributed, collaborative, hypertext information
    systems.  This document defines the semantics of HTTP/1.1 messages,
    as expressed by request methods, request header fields, response
    status codes, and response header fields, along with the payload of
    messages (metadata and body content) and mechanisms for content
    negotiation.

 
RFC 7231             HTTP/1.1 Semantics and Content            June 2014


6.5.1.  400 Bad Request

    The 400 (Bad Request) status code indicates that the server cannot or
    will not process the request due to something that is perceived to be
    a client error (e.g., malformed request syntax, invalid request
    message framing, or deceptive request routing).




Fielding & Reschke           Standards Track                   [Page 58]