What is a Moped?

What is a Moped? A Moped is a cross between a bicycle and a motorbike. It is powered by a small engine and also have a pedal. On Season 1, Episode 17 of "My Name Is Earl", Crabman spotted Randy sitting on a Moped and commented,

"Thats a cool Moped, Randy. It looks like a motorbike had sex with a bicycle"