Error pages are webpages that automatically appear when something goes wrong with the website. The user will see a different HTTP error message depending on what went wrong. A 404-Error code, for example, means the server could not find the requested page. Error 401means the website visitor does not have authorization to visit the requested page. Error 400 signifies a bad request. Website developers can customize error pages if desired, to say something funny or witty that may lighten an inconvenient situation for irritated users and decrease bounce rates. Detecting and fixing error pages can help improve a website’s search engine ranking.