This document discusses the different types of simple machines: levers, pulleys, inclined planes, screws, wedges, and wheels and axles. It describes the key components and functions of each machine. First class levers gain speed and distance at the expense of force, while second class levers gain force with a loss of speed and distance. Pulleys can change the direction of an applied force but do not gain mechanical advantage. Inclined planes reduce the amount of force needed to move an object by increasing the distance moved. Screws convert rotational motion to linear motion, while wedges concentrate force into a narrow space. Wheels and axles function like a rotating lever.
