The Milky Way is the galaxy that contains our solar system. Earth is just one of billions (or maybe even trillions) of planets in the Milky Way.
On a dark night, far from bright city lights, you can see the Milky Way in the sky. With the naked eye, it looks like a hazy band of light. We can't view the entire galaxy, though, because we're part of it! Ancient stargazers suspected that they were observing stars, and the name Milky Way was inspired by its milky-white color. Middle English variations included Milken-Way, Milk-white girdle, and Milky Cercle.