This document defines and describes different types of gears used to transmit power between parallel or intersecting shafts, including spur gears, helical gears, bevel gears, worm gears, and gear trains. It also explains the components and functioning of single plate clutches used to connect driving and driven shafts, allowing the driven shaft to be engaged and disengaged without stopping the driving shaft. Finally, it provides details on friction discs used for power transmission where only small amounts of power need to be transferred and slippage can occur under higher loads.