Knowledge
HTTP Status Codes
What 200, 301, 404 and 500 mean – all codes explained
CodeNameDescription
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HTTP status codes – server responses explained

HTTP status codes are three-digit numbers that servers send in response to browser requests. They are grouped into five classes: 1xx (informational), 2xx (success), 3xx (redirection), 4xx (client errors) and 5xx (server errors). The most common codes are 200 (OK), 301 (permanent redirect), 404 (not found) and 500 (internal server error). Understanding status codes helps diagnose web issues and is essential for web development and SEO.