Why Do Rainbows Appear After a Storm?

Rainbows happen when sunlight plays hide-and-seek with raindrops. After it rains, there are lots of tiny water droplets in the air. When sunlight hits these droplets, they bend the light, like a prism in a classroom. This bending splits white sunlight into all its colors: red, orange, yellow, green, blue, indigo, and violet. That's how we see a rainbow as an arc in the sky. You need the sun behind you and raindrops in front of you for it to show up!