Web Development Beginner

What is HTTP Status Codes?

Standardized three-digit codes returned by web servers to indicate the result of a client's HTTP request.

Status codes are grouped: 1xx (informational), 2xx (success), 3xx (redirection), 4xx (client error), 5xx (server error). Essential codes: 200 OK, 201 Created, 204 No Content, 301 Moved Permanently, 302 Found, 400 Bad Request, 401 Unauthorized, 403 Forbidden, 404 Not Found, 409 Conflict, 429 Too Many Requests, 500 Internal Server Error, 502 Bad Gateway, 503 Service Unavailable.

Proper status code usage is critical for REST API design. Clients and monitoring tools rely on codes to determine success or failure. Using 200 for error responses is an anti-pattern — return appropriate error codes with descriptive messages.

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