A roller coaster, e.g., is a type of amusement RIDE that typically consists of a series of cars that move along a winding track. The cars are often designed to resemble trains and they are propelled by gravity and momentum. Riders experience sudden drops and sharp turns as the cars move along the track. Roller coasters are popular attractions at amusement parks and other entertainment venues. The term for this type of RIDE is 'RIDE' with four letters.