404 Error Page
Noun · Hacker Culture
Definitions
404 Error Page is the web page displayed to users when they attempt to access a URL that does not exist on a server, corresponding to the HTTP 404 Not Found status code. While the default server-generated 404 page is typically a plain, unhelpful error message, well-designed custom 404 pages have become a creative opportunity and a mark of thoughtful web design. Effective 404 pages include a clear message explaining that the requested page was not found, a search bar to help users find what they were looking for, links to popular pages or the homepage, consistent branding and navigation, and sometimes humor or interactive elements. Notable creative examples include GitHub's parallax Star Wars scene, Blizzard's page featuring game characters, and Pixar's crying character from Inside Out. From an SEO perspective, returning a proper 404 status code (not a soft 404 that returns a 200 status) helps search engines correctly identify missing pages. Monitoring 404 errors in server logs helps webmasters identify and fix broken links.
In plain English: The 'page not found' screen you see when you visit a web address that doesn't exist, often customized to be funny or helpful.
Example: "Our 404 page has a little game where you guide a lost astronaut back to the homepage — bounce rate on that page actually dropped."