HTTP error/server response codes reference

Below is a brief explanation of various common HTTP browser error codes and server response codes.   

Code Number	Browser Error Message	Description
200	none	This is the normal response where a page has been successfully fetched
301	none	Page has moved permanently. usually a response from implementing a 301 redirect
302	none	Page has moved temporarily
304	none	Page has not been modified since last request (this is an OK response)
400	Bad Request	The request could not be understood by the server due to incorrect syntax.
401	Unauthorized User	authentication is required.
403	Forbidden	The server understood the request, but is refusing to fulfill it.
404	Page Not Found	The server has not found anything matching the Request-URI.
405	Method Not Allowed	The method specified in the Request-Line is not allowed for the resource identified by the Request-URI.
406	Not Acceptable	The server cannot generate a response that the requestor is willing to accept.
407	Proxy Authentication Required	This code is similar to 401 (Unauthorized), but indicates that the client must first authenticate itself with the proxy.
408	Request Timed Out	The server stopped waiting for a client request.
409	Conflict	The request could not be completed due to a conflict with the current state of the resource.
410	Gone	The requested resource is no longer available at the server and no forwarding address is known. This condition is similar to 404, except that the 410 error condition is expected to be permanent.
411.	Length Required	The server requires a content-length in the request
412	Precondition Failed	The precondition given in one or more of the request-header fields evaluated to false when it was tested on the server.
413	Request Entity Too Large	The server is refusing to process a request because the request entity is larger than the server is willing or able to process.
414	Request URL Too Long	The server is refusing to service the request because the Request-URI is longer than the server is willing to interpret.
415	Unsupported Media Type	The server is refusing to service the request because the entity of the request is in a format not supported by the requested resource for the requested method.
500	Server Error	Internal Web server error
501	No Server	Function not implemented in Web server software
502	Server Overload	Bad Gateway; a server being used by this Web server has sent an invalid response.
503	Service Unavailable	Service unavailable because of temporary overload or maintenance.
504	Gateway Timeout	A server being used by this server has not responded in time.
505	HTTP Version Not Supported	The server does not support the HTTP protocol version that was used in the request message.