The bonk comes from classic cartoon slapstick, where exaggerated impact noises replaced realistic hits so gags stayed light and readable for children. Animators paired hollow knocks, boings and slides with bumps long before home video editing, and the same library-style bonk later spread through flash animations, YouTube edits and meme soundboards. Unlike a realistic punch sound, this effect stays playful rather than violent, which is why creators still reach for it for pratfalls, gaming fails and reaction clips where the joke is clumsiness, not injury or damage at all.