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What are HTTP response status codes?
HTTP Status Code (HTTP Status Code) is a 3-digit code indicating the response status of the web server Hypertext Transfer Protocol
HTTP response codes are divided into five categories
- Information response (100~199)
- Successful response (200~299)
- Redirect response (300~399)
- Client error response (400~499)
- Server error response (500~599)
Ten common HTTP status codes
- 200 = "OK (success) The request is successful and the normal status is our most common status code.
- 301 = "Moved Permanently" The URL of the requested resource has been permanently changed. The new URL is given in the response.
- 302 = "Found Temporary redirection, indicating that the URI of the requested resource has been temporarily changed, and the client can continue to access this address in the future.
- 303 = "See Other" must be redirected, indicating that the client obtains the requested resource in another URI through a GET request.
- 304 = "Not Modified" means that it has not been modified. The current resource has been downloaded and has not been modified. The client can obtain the resource from the cache. Generally only used for GET requests, such as requesting HTML resources.
- 401 = "unauthorized (unauthenticated), indicating that the protocol is wrong and access is denied. The client must authenticate itself to obtain a response to the request. Common scenarios: refresh a page frequently, or crawlers visit a certain page in large numbers Restricted by anti-climbing.
- 403 => Forbidden (not allowed) means that there is no permission to access, and the server rejects the access request.
- 404 => Not Found (not found) means that the system resource cannot be found.
- 500 => Internal Server Error (internal service error) indicates a server program error.
- 503 => Service Unavailable means the server is busy.