The four fundamental forces in nature are the gravitational force, electromagnetic force, strong nuclear force, and weak nuclear force. The gravitational force is the attraction between masses, governing the motion of celestial bodies. Electromagnetic force operates between charged particles and is responsible for electricity, magnetism, and chemical bonding. The strong nuclear force holds protons and neutrons together in atomic nuclei, while the weak nuclear force is involved in the process of nuclear decay and plays a role in reactions like beta decay. Together, these forces explain a wide range of physical phenomena and the structure of matter.