HTTP response status codes indicate whether a specific HTTP request has been successfully completed. Responses are grouped in five classes:
- Informational responses (1XX)
- Successful responses (2XX)
- Redirections (3XX)
- Client errors (4XX)
- Server errors (5XX)
a) Informational responses: Status codes under this category indicate whether the request was received and understood.
The following list below shows informational responses.
100: Continue
101: Switching Protocols
102: Processing
103: Early Hints
b) Successful responses: Status codes under this category indicate whether the request was successfully received, understood and accepted.
The following list below shows successful responses.
200: OK
201: Created
202: Accepted
203: Non-Authoritative Information
204: No Content
205: Reset Content
206: Partial Content
207: Multi-Status
208: Already Reported
226: IM Used
c) Redirections: Status codes under this category indicate that further actions need to be taken to complete the request.
The following list below shows redirections.
300: Multiple Choices
301: Moved Permanently
302: Found
303: See Other
304: Not Modified
305: Use Proxy
306: Switch Proxy
307: Temporary Redirect
308: Permanent Redirect
d) Client errors: Status codes under this category indicate errors caused by the client.
The following list below shows client errors.
400: Bad request
401: Unauthorized
402: Payment required
403: Forbidden
404: Not found
405: Method not allowed
406: Not acceptable
410: Gone
e) Server errors: Status codes under this category indicate errors caused by the server.
The following list below shows server errors.
500: Internal server error
501: Not implemented
502: Bad gateway
503: Service unavailable
504: Gateway timeout
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