The power that drives a machine is usually transmitted in one of three ways: (1) from a fly-wheel in the power house to a pulley on a main line of shafting in the shop and then to another pulley on a small shaft over each machine, called a countershaft; (2) directly from the pulley of an electric motor, located in the shop where it drives the main line of shafting; or (3) by means of gears from a separate electric motor attached to each machine. The first two methods are called power transmission by shafting, and the third is called power transmission by separate motor or "individual drive."