PORTLAND, OR— Until the invention of the Phillips screw, American assembly lines, craftsmen, and consumers used regular, slotted-head screws. But that design was problematic for three reasons: it was difficult to align the driver with the screw aperture; the driver tended to slip from the open ends; and the slot required a closely matching bit. The cruciform drive addressed those problems. 

Ever-increasing internal and external drive styles give design engineers more ways to effectively transfer torque from tool to fastener.