Error pages are web pages which are displayed when an error occurs. The error page alerts the user to the type of error which occurred, and may make suggestions for steps the user can take to resolve the issue. In addition to basic pages which provide error information on an unstyled web page, it is also possible to use custom error pages which can be designed with extra features and a styled appearance. These settings can be changed at the server; many servers provide utilities which can be used to generate custom error pages.
Many Internet users are familiar with the infamous 404: Not Found error page. This is one of the most commonly seen error pages. Like other errors in the 400 range, the 404 is returned when an error is made on the client's side. Many websites use customized 404 pages which suggest alternate spellings of the link, provide a search box so that people can try to locate the resource they were attempting to reach, or redirect the user to the main page.
When server errors occur, an error page in the 500 range will be displayed. Error pages in the 300 range are displayed when there is a redirect or change. Many of these pages provide users with multiple options which they can select from to attempt to reach the desired resource. All of these pages can be customized to provide more utility or to look more visually interesting.
Customized error pages can range from the whimsical to the simple and practical, depending on the tastes of the web designer and the needs of the website itself. Some designers enjoy making error pages which demonstrate a sense of humor, and they may add a silly as well as a useful aspect to their error pages. Organizations which collect examples of interesting, innovative, or simply funny web design often have collections dedicated to custom error pages of particular note.
Some websites will not display errors, or will only display error pages in a range of numbers. This is sometimes done in an attempt to repel hackers; rather than being able to see an error page which might provide information about what they are doing, the hacker would be bumped back to the main page. This can sometimes be frustrating for legitimate users, however, as they may not understand why they are encountering errors, and will not be aware of steps they might be able to take to address the error.