While certain TV series have been hits with audiences and critics alike only to be cancelled after one or a handful of seasons, (from My So-Called Life and Freaks and Geeks to Mindhunter), others just keep coming back. ABC’s medical drama Grey’s Anatomy is embarking on its 20th season, and the animated series Family Guy was renewed for its 23rd, appearing on Fox since 1999.
Source: The longest-running TV series in every category – from soaps to sitcoms