TaylorMade revolutionized the driver like nobody before them and likely anyone after them. From the beginning of golf, ~1457, up to 1979 drivers were all made with wood, typically persimmon. Before TaylorMade manufactured the head of a driver out of steel, virtually all drivers were made out persimmon wood. That's why we call them woods. In 1979 TaylorMade introduced the metal head and called it a "Pittsburgh Persimmon." That name is so clever. Pittsburgh, the steel city; Persimmon, the wood used to make drivers. That amuses me. Whether they knew they were going to change the game or not, they did. Steel was stronger than wood, so they could hollow the head out of steel clubs and make them much lighter than their counterparts. From there they could also make them bigger, bigger club head equals bigger sweet spot. Steel isn't a primary component anymore because stronger, lighter elements or alloys are now employed. The transitions since wood to steel have come hot and fast; alloys, titanium, and now some brands are even adopting carbon fiber. The Stealth 2 driver is able to run because the Pittsburgh Persimmon driver got up and walked. If you're using a modern driver, pay homage to TaylorMade. They did it first and they do it best.