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The earth continuously spins in space. But we did not fall off the surface of the earth. We can move on it like flies walking on a tennis ball. Why don't we fall off? The earth contains an enormous amount of matter. It's mass is great. Every particle of matter on the earth pulls on every other particle of matter. We call this pulling force gravity. This force of gravity keeps us form fallin off the earth.
The gravitational pull of the ball is very important. Through this various works are being done in the world.