Passenger ship in the context of "RMS Saxonia (1899)"

Cruise ships are large passenger ships used mainly for vacationing. Unlike ocean liners, which are used for transport, cruise ships typically embark on round-trip voyages to various ports of call, where passengers may go on tours known as "shore excursions".

Modern cruise ships tend to have less hull strength, speed, and agility compared to ocean liners. However, they have added amenities to cater to water tourists, with recent vessels being described as "balcony-laden floating condominiums".

An ocean liner is a type of passenger ship primarily used for transportation across seas or oceans. Ocean liners may also carry cargo or mail, and may sometimes be used for other purposes (such as for pleasure cruises or as hospital ships). The Queen Mary 2 is the only active ocean liner in 2025, serving with Cunard Line.

The category does not include ferries or other vessels engaged in short-sea trading, nor dedicated cruise ships where the voyage itself, and not transportation, is the primary purpose of the trip. Nor does it include tramp steamers, even those equipped to handle limited numbers of passengers. Some shipping companies refer to themselves as "lines" and their passenger ships, which often operate over set routes according to established schedules, as "liners".

A mooring is any permanent structure to which a seaborne vessel (such as a boat, ship, or amphibious aircraft) may be secured. Examples include quays, wharfs, jetties, piers, anchor buoys, and mooring buoys. A ship is secured to a mooring to forestall free movement of the ship on the water. An anchor mooring fixes a vessel's position relative to a point on the bottom of a waterway without connecting the vessel to shore. As a verb, mooring refers to the act of attaching a vessel to a mooring.

The term likely stems from the Dutch verb meren (to moor), used in English since the end of the 15th century.

First class is the most luxurious and most expensive travel class of seats and service on a train, passenger ship, airplane, bus, or other system of transport. Compared to business class and economy class, it offers the best service and most comfortable accommodation.

Sealift is a term used predominantly in military logistics and refers to the use of cargo ships for the deployment of military assets, such as weaponry, vehicles, military personnel, and supplies. It complements other means of transport, such as strategic airlifts, in order to enhance a state's ability to project power.

Sealift shipping falls into three broad categories: dry cargo freighters, liquid tankers, and passenger or troop ships. During joint operations, dry cargo ships may transport equipment and supplies required to conduct and sustain the operation; tankers carry fuel; while passenger and troop ships carry personnel to the theater and allow the evacuation of noncombatants or those in need of medical aid.