The gravitational constant, denoted as G, is a fundamental physical constant that measures the strength of gravity in the universe. It is used in the law of universal gravitation, which describes how two masses attract each other. The value of G is approximately 6.674 × 10⁻¹¹ N(m/kg)², where N is newtons, m is meters, and kg is kilograms. This constant plays a crucial role in various scientific calculations, including those related to the orbits of planets, the behavior of stars, and the dynamics of galaxies. Understanding G helps scientists explore the nature of gravity and its effects on the cosmos.