Anything with mass has a gravitational pull, the larger the object, the harder the pull. Earths gravitational pull is about 9.8. because of its size and mass. but the moons gravitational pull is much less, because the moon is much smaller than the earth. but now lets talk about central force, lets take a ride at an amusement park for example, you know the one im talking about, the ride where you go into, and it start spinning so fast that you get sucked, and stuck to the side until it stops spinning. gravity works much similarly, the earth actual spins about 1000mph (1609.344 km) while we do not feel this, if the earth where to stop spinning, the gravitational pull would be much less to none. but in this scenario, we would have far worse problems than gravity.