The force that pulls objects towards Earth's surface is gravity.

Here's a breakdown:

* Gravity is a fundamental force of nature that attracts any two objects with mass.

* The more massive an object, the stronger its gravitational pull. Earth is a very massive object, so it exerts a strong gravitational force on everything around it.

* This force is what keeps us on the ground, what causes objects to fall when dropped, and what holds the moon in orbit around Earth.

Let me know if you have any other questions about gravity!