The 'one hour later' time card comes from SpongeBob SquarePants, where the French narrator marks time passing between scenes. Clips of the card became a classic meme sound as creators lifted the narration to fake time skips in their own videos. It spread through YouTube compilations and reaction edits in the 2010s because it compresses a whole montage into two words. It is still used today whenever a creator wants an instantly understood shortcut for 'meanwhile'.