Cruise lines are companies that operate cruise ships, providing vacation experiences on the water. These ships travel to various destinations, offering passengers a chance to explore different ports while enjoying onboard amenities like restaurants, entertainment, and recreational activities. Popular cruise lines include Carnival, Royal Caribbean, and Norwegian. Passengers can choose from various cruise itineraries, ranging from short weekend trips to longer voyages that last several weeks. Many cruise lines cater to specific demographics, such as families, couples, or luxury travelers, ensuring a tailored experience for different types of vacationers.