This document provides information about springs and flywheels. It defines springs as elastic bodies that distort under load and recover their original shape when unloaded. Common types of springs discussed include helical, leaf, and Belleville springs. Terminology used in helical springs like wire diameter, coil diameter, and spring index are defined. The document also discusses flywheels, their purpose of storing energy from the power source and releasing it more uniformly. Equations for coefficient of fluctuation of speed and energy, work done per cycle, and energy stored in a flywheel are provided.