Here's a breakdown:

* Gravity: This is a fundamental force of nature that attracts any two objects with mass. The more massive the objects, the stronger the gravitational attraction.

* Orbital Motion: Planets don't just fly off in straight lines because of the Sun's gravity. The Sun's gravitational pull constantly pulls the planet towards it, but the planet is also moving sideways. This combination of a sideways motion and the Sun's pull creates a curved path, which is the orbit.

Imagine throwing a ball horizontally. The ball would fall to the ground due to gravity. Now, imagine throwing the ball harder. It would travel further before hitting the ground. If you could throw it fast enough, it would travel so far that the Earth would curve away beneath it, and the ball would theoretically never hit the ground. This is similar to how planets orbit, except they are constantly being pulled by the Sun's gravity.