Model M keyboards are a group of computer keyboards designed and manufactured by IBM starting in 1985, and later by Lexmark International, Maxi Switch, and Unicomp. The keyboard's different variations have their own distinct characteristics, with the vast majority having a buckling-spring key design and uniform profile, swappable keycaps. Model M keyboards are notable among computer enthusiasts and frequent typists due to their durability, typing-feel consistency, and their tactile and auditory feedback.