Roll on roll off

Roll-on roll-off (ro-ro) is a cargo-handling method where wheeled units drive or are towed on and off the ship across ramps, without crane lifting. Vehicles and trailers load through stern, side, or quarter ramps onto continuous vehicle decks and are lashed for the voyage, which makes loading and discharge fast at ramp-equipped berths. Ro-ro ships range from pure car and truck carriers to ro-pax ferries and con-ro hybrids that also carry containers. It contrasts with lift-on lift-off (lo-lo) container handling and is the standard mode for cars, trailers, and self-propelled project units. Capacity is measured in lane meters.