* Centripetal Force: This is the force that pulls an object towards the center of a circle. In the case of planets, the centripetal force is provided by gravity, the attraction between the planet and the star it orbits.

* Centrifugal Force: This is an apparent force that pushes an object outwards as it moves in a circle. It's not a real force but rather the result of inertia.

The Balance:

* If only centripetal force (gravity) acted on a planet, it would fall straight into the star.

* If only centrifugal force acted, the planet would fly off in a straight line.

It's the balance between these two forces that keeps planets in orbit.

* Gravity (centripetal force) pulls the planet towards the star, while the planet's inertia (centrifugal force) tries to keep it moving in a straight line.

* The result is a curved path, or an orbit, around the star.

In summary, a planet's orbit is a balance between the centripetal force of gravity and the centrifugal force due to its inertia.