A kazoo is a simple musical instrument that changes the sound of your voice into a buzzing, humming tone. When you hum into the wide end of a kazoo, a thin membrane inside vibrates and creates that distinctive buzzy sound that's funny and musical at the same time.

Kazoos are usually small, lightweight tubes made of plastic or metal, shaped a bit like a submarine with a hole on top. You don't blow into a kazoo like a trumpet or whistle. Instead, you hum or sing into it, and the kazoo transforms your voice into something that sounds like a cross between a duck and a tiny trombone.

Because kazoos are so easy to play, they're popular instruments for kids, parades, and playful music. You don't need to learn finger positions or read sheet music. If you can hum “Happy Birthday,” you can play it on a kazoo. Some musicians even use kazoos seriously in folk bands and jazz groups, proving that simple instruments can make joyful, memorable music.