In computer network communications , the HTTP 404 , 404 not found , 404 , 404 error , page not found or file not found error message is a hypertext transfer protocol (HTTP) standard response code , to indicate that the browser was able to communicate with a given server , but the server could not find what was requested. The error may also be used when a server does not wish to disclose whether it has the requested information. [1]
The website hosting server will typically generate a "404 Not Found" web page when a user attempts to follow a broken or dead link ; hence the 404 error is one of the most recognizable errors encountered on the World Wide Web .
When communicating via HTTP, a server is required to respond to a request, such as a web browser request for a web page , with a numeric response code and an optional, mandatory, or disallowed (based upon the status code) message. In code 404, the first digit indicates a client error, such as a mistyped Uniform Resource Locator (URL). The following two digits indicate the specific error encountered. HTTP's use of three-digit codes is similar to the use of such codes in earlier protocols such as FTP and NNTP