Precession is the gradual change in the orientation of an object's rotational axis. For example, the Earth's axis wobbles slightly over time, which affects the position of the poles. This phenomenon occurs due to gravitational forces exerted by the Moon and Sun on the Earth's equatorial bulge. The most well-known type of precession is the axial precession of the Earth, which takes about 26,000 years to complete one cycle. This slow movement causes the positions of the stars to shift over millennia, influencing navigation and astronomy.