Gravity attracts objects that have mass and pulls them toward the center of the Earth. Everything on Earth is held by gravity including the atmosphere.
On Earth, any object that has mass has gravitational pull; this is called force. Gravitational forces are forces of attraction. The strength of the gravitational force depends on the mass of the object and its proximity to the Earth. The larger and closer the object, the greater the gravitational pull.
Gravitational force on the Earth cause objects to accelerate when they fall. The Earth’s gravity produces the same amount of acceleration on all objects, and they gain velocity at the same rate. Gravity pulls the objects toward the Earth, and they speed up as they get closer to the Earth.
Gravitational pull from the sun keeps the Earth in orbit. The gravity exerted by the moon causes the rise and fall of the tides. When the moon is over an ocean, the sea level swells.
Gravity keeps all cosmic bodies from free-floating in space and causes drifting particles to pull together and become planets and stars. The force of gravity is so strong around black holes in space that not even light can escape its effects.