HTTP status code refers to a three-digit code returned by the server when responding to a client request in the HTTP protocol. It is used to inform the client of the processing results of the request so that the client can take corresponding processing measures based on different status codes.
HTTP status code consists of three digits. The first number defines the category of status code, which is divided into the following five categories:
1xx (Informational status code): Indicates Request received and being processed.
2xx (success status code): Indicates that the request was processed normally.
3xx (redirect status code): Indicates that further action is required to complete the request.
4xx (client error status code): Indicates that the request sent by the client has an error.
5xx (server error status code): Indicates that an error occurred when the server processed the request.
The specific meaning of each status code has given common examples in the previous answers.
Through the HTTP status code, the client can understand the server's processing results of the request, and can make corresponding processing based on the status code. For example, for status code 200, the client can know that the request is successful; for status code 404, the client can know that the requested page does not exist; for status code 500, the client can know that an internal error has occurred in the server, etc.
HTTP status code is a very important part of the HTTP protocol. It provides a standardized way to represent and transmit the results of request processing, and provides specifications for communication between the client and the server.