Luigi is Nintendo's green-clad younger brother of Mario, first introduced in the arcade game Mario Bros. and later made famous in the Super Mario series. Over decades he grew from a simple palette swap into a beloved character in his own right, known for his nervous charm and loyal personality. The shouted version of his name became a staple in gaming memes, reaction videos and short-form edits, where fans use it to signal his arrival or poke fun at his underdog status. Its instant recognisability keeps it popular across generations of players.