HTTP response status codes

statuses.md

Code	Definition	Meaning
1xx	Informational	Received request, continuing process.
2xx	Success	The action requested was received, understood, accepted and processed.
200	OK	Action completed successfully.
3xx	Redirection	The client must take additional action for the request to be completed
302	Found	The requested URI was found. Sometimes results in a redirect, similarly to 303 See Other
303	See Other	The response can be found under another URI. Assume the server received the data.
304	Not Modified	A cached version of the requested file is the same as the file to be sent.
4xx	Client Error	The client seems to have erred.
400	Bad request	There was a perceived client error in the request, ex. malformed syntax.
401	Unauthorized	Authentication is required and has failed or not yet been provided.
403	Forbidden	Directory or file does not have the permission to allow web viewing.
404	Not Found	The requested file was not found.
418	I'm a teapot	A request to brew coffee was sent to a tea pot.
429	Too Many Requests	The user has sent too many requests during a period of time
5xx	Server Error	The server failed to fulfill a valid request.
503	Out of Resources	The server can not or will not process the request due to system overload.
504	Gateway Time-Out	The service did not respond in the time frame the gateway was willing to wait.