A Ro-Ro ship is a ship that enables the loading and unloading of cargo in a horizontal transhipment method with the help of wheels and transhipment ramps. Passenger Ro-Ro ships are used to transport passengers and vehicles, but at the same time, they can also transport containers or other goods. The role of passenger liner shipping for a maritime country like Croatia is extremely important since 3.3% of the population lives on the islands, and during the tourist season, this number increases significantly. In the Republic of Croatia, public liner shipping of passengers and wheeled cargo is mostly performed by the company Jadrolinija. Jadrolinija's fleet includes 39 ferries, 12 catamarans, 4 classic ships and one ferry on international lines. Jadrolinija's main task is to connect the islands with the mainland on the Croatian side of the Adriatic. Jadrolinija's transporting of passengers and vehicles is highly seasonal and heavily influenced by tourism. Jadrolinija's white fleet annually transports over 12 million passengers and three million vehicles, making up over 80% of the annual number of all transported passengers and vehicles in the Republic of Croatia maritime transport.