What is a gyroscope?

A gyroscope is any rotating body that exhibits two properties: gyroscopic inertia or rigidity in space and precession or the tilting of the axis at right angles to any force tending to alter the plane of rotation. These properties are inherent in all rotating bodies, including the Earth. The term gyroscope is applied to spherical, wheel-shaped or disk-shaped bodies universally mounted to be free to rotate in any direction. They are used to demonstrate these properties or to indicate movements in space. A gyroscope constrained from moving around one axis other than the axis of rotation is called a gyrostat.