1. Revolution: This is the movement of a planet around the Sun in an elliptical orbit. Think of it like the Earth going around the Sun, completing one full circle every year. This is the movement that determines a planet's year.

2. Rotation: This is the spinning of a planet on its axis. Think of the Earth spinning on its axis, causing day and night. This movement determines a planet's day.

Let me know if you want to learn more about these movements!