Moved to Atlanta is Internet slang for the 404 status code, the frequently seen "page not found" error.
A page that is not found is said to have moved to Atlanta. The reference is to Atlanta's 404 area code. 404 and other status codes are part of the Web's HTTP (Hypertext Transfer Protocol), written in 1992 by the Web's inventor, Tim Berners-Lee.
Browsers have default pages for 404 errors, usually informing the user that the requested page was not found, listing the probable causes and providing a link to the site's home page. However, site owners can also develop custom 404 pages to align with their website's style, guide the user and/or provide entertainment.
Help users with your 404 pages: