With ships travelling between Europe and North America, the busiest route for liners was on the North Atlantic. Ocean liners are usually built strongly with a high freeboard to withstand rough rear and adverse conditions encountered in the open ocean.
The largest and most advanced liners travelled on these routes. Early ocean liners had sails as well as the engines to supplement the inefficient consumption of fuel. Even those cargo vessels running to a schedule are referred to as liners. They follow a regular long distance maritime route and a fixed schedule. Initial inefficiency and disadvantages overt sailing ships was the appearance of steam engines in ships. For over a century Ocean liners were used as the major mode of intercontinental travel until they began to be home elevators Suppliers supplanted by airliners. Voyage dedicated cruise ships where transportation is not the primary purpose, or ferries and other vessels that indulge in short sea trading do not fit the category.
True ocean liner characteristics include heavier plating, robust scant lings, powerful engines and high freeboard making them for seaworthy than vessels designed for short real routes or cruises in protected waters. Other common terms used interchangeably with ocean liners are passenger liner, cargo liner or cargo passenger liners. There liners have large capacities for fuel, victuals and other stores for consumption on long voyages. Liners are sometimes used for other purposes and also to carry cargo or mail. Liners were the most preferred way to note gold and other high value cargoes. Tramp streamers with equipment for a limited number of passengers are not considered as ocean liners. Unlike the clippers, streamers offered consistent speed and the ability to keep to a schedule.
The golden age of ocean liners was considered as the period post the end of World War II, driven by the strong demand created by international competition between passenger lines.
Container ships that often operate over set routes according to schedules are also referred to as liners and the shipping companies that own these vessels are known as lines.
Ocean liners are ships designed to transport people from one seaport to another. Modern day usage of the term is to refer to a ship that is constructed to a higher standard than a normal cruise ship, that may not be able to embark in inclement conditions to cross oceans such as the Atlantic and Pacific.