301，404，200，304等HTTP状态，代表什么意思

代表http服务器返回的状态301 被请求的资源已永久移动到新位置404 请求失败200 OK304 文档的内容（自上次访问以来或者根据请求的条件）并没有改变1定义2消息（1字头）▪100 Continue▪101 Switching Protocols▪102 Processing3成功（2字头）▪200 OK▪201 Created▪202 Accepted▪203 Non-Authoritative Information▪204 No Content▪205 Reset Content▪206 Partial Content▪207 Multi-Status4重定向（3字头）▪300 Multiple Choices▪301 Moved Permanently▪302 Move temporarily▪303 See Other▪304 Not Modified▪305 Use Proxy▪306 Switch Proxy▪307 Temporary Redirect5请求错误（4字头）▪400 Bad Request▪401 Unauthorized▪402 Payment Required▪403 Forbidden▪404 Not Found▪405 Method Not Allowed▪406 Not Acceptable▪407 Proxy Authentication Required▪408 Request Timeout▪409 Conflict▪410 Gone▪411 Length Required▪412 Precondition Failed▪413 Request Entity Too Large▪414 Request-URI Too Long▪415 Unsupported Media Type▪416 Requested Range Not Satisfiable▪417 Expectation Failed▪421There are too many connections from your internet address▪422 Unprocessable Entity▪423 Locked▪424 Failed Dependency▪425 Unordered Collection▪426 Upgrade Required▪449 Retry With6服务器错误（5字头）▪500 Internal Server Error▪501 Not Implemented▪502 Bad Gateway▪503 Service Unavailable▪504 Gateway Timeout▪505 HTTP Version Not Supported▪506 Variant Also Negotiates▪507 Insufficient Storage▪509 Bandwidth Limit Exceeded▪510 Not Extended▪600 Unparseable Response Headers