In physics, gravity (from Latin gravitas 'weight') is a fundamental
interaction which causes mutual attraction between all things that have mass.
Gravity is, by far, the weakest of the four fundamental interactions,
approximately 1038 times weaker than the strong interaction, 1036 times weaker
than the electromagnetic force and 1029 times weaker than the weak
interaction. As a result, it has no significant influence at the level of
subatomic particles. However, gravity is the most significant interaction
between objects at the macroscopic scale, and it determines the motion of
planets, stars, galaxies, and even light.