Thumb a ride, also known as hitchhiking or hitching, is a form of transportation in which a person stands by the side of the road and signals to passing vehicles to ask for a ride. It is also sometimes referred to as 'bumming a ride' or simply 'bumming'. The term 'thumb a ride' comes from the gesture of extending one's thumb to signal a vehicle to stop. Hitchhiking is a popular form of transportation in many parts of the world, and has been used for centuries.