A cruise ship is a passenger ship used for pleasure voyages when the voyage itself, the ship's amenities, and sometimes the different destinations along the way (i.e., ports of call), form part of the passengers' experience. Transportation is not the only purpose of cruising, particularly on cruises that return passengers to their originating port. On "cruises to nowhere" or "nowhere voyages", cruise ships make 2-to-3 night round trips without any ports of call.
Although often luxurious, ocean liners had characteristics that made them unsuitable for cruising, such as high fuel-consumption, deep draughts that prevented their entering shallow ports, enclosed weatherproof decks inappropriate for tropical weather, and cabins designed to maximize passenger numbers rather than comfort (such as a high proportion of
windowless suites). The gradual evolution of passenger-ship design from ocean liners to cruise ships has seen passenger cabins shifted from inside the hull to the superstructure and provided with private verandas. Modern cruise ships, while sacrificing some qualities of seaworthiness, have added amenities to cater to water tourists, and recent vessels have been described as "balcony-laden floating condominiums"