Portal is Valve's first-person puzzle series, first released in 2007, built around test chambers, portals and the Aperture Science turrets that guard them. The turrets are small tripod robots with a polite, feminine, robotic voice, and their calm lines became one of the games' most quoted features. Short clips like this one spread through gaming videos, edits and soundboards, where players reuse the turrets' deadpan delivery for jokes about sleep, shutdowns and tired opponents. Its brevity and instantly recognisable Portal tone keep it useful years after the games first appeared.