Mario and Luigi are the long-running brother duo at the centre of Nintendo's Super Mario series, with Mario as the lead hero and Luigi as his taller, often more cautious brother. Their pairing has become shorthand online for teamwork, sibling humour and co-operative play, appearing in gameplay videos, memes and edits that feature two people working together. Because the duo is instantly recognisable across generations of players, a short clip naming or celebrating them still works as a quick, friendly signal for a partnership, even in a video that has nothing to do with a Mario game.