404 error
404 File Not Found is a message that appears in most web browsers when a URL that leads to a page that does not exist on the webserver addressed in the URL, leading to a "404 error".The 404 error is one of the standard response codes of the web's HTTP protocol. The first 4 indicates a client error such as a mistyped URL. The middle 0 refers to a general syntax error. The last 4 just indicates the specific error in the group of 40x, which in this case is "URL Not Found". The use of three-digit codes is similar to the use of such codes in earlier protocols such as FTP and NNTP.
Note that a 404 error only occurs when the URL addresses a server that is actually running an HTTP server; otherwise, other messages are generated.
To see a "404 screen," one can click on this "go-nowhere link": http://www.whitehouse.gov/~saddam/ The "404 screen" is often parodied on other websites.
Examples:
Includes material from FOLDOC, used with permission. Update as needed.
