Air horns began as handheld, compressed-air horns used on boats and at sporting events to signal starts, goals and warnings across noisy crowds. That same unmistakable blast moved online in the 2010s, when editors and streamers adopted it for MLG-style montages, prank videos and reaction edits. Its association with stadium celebrations and internet hype kept it in constant circulation on soundboards and social video, where a four-second blast still functions as instant shorthand for excitement, interruption or an exaggerated celebration that needs no explanation.