The nuclear force, also known as the strong nuclear force, is one of the four fundamental forces of nature. It is responsible for holding the protons and neutrons together in the nucleus of an atom. This force is incredibly strong but acts over very short distances, typically on the order of a femtometer (10^-15 meters). The nuclear force overcomes the electromagnetic repulsion between positively charged protons, allowing atomic nuclei to remain stable. Without this force, atoms would not exist as we know them, and matter would be fundamentally different. Understanding the nuclear force is essential in fields like nuclear physics and particle physics.