A cruise ship (or cruise liner or ocean liner, though the latter mainly refers to cruise ships which cross the ocean) is a large ship with sleeping cabins and other facilities that takes people on holiday and vacation trips. Hundreds of thousands of people take cruises each year.
Today's cruise ships are like floating hotels. They have a complete "hospitality staff" (to serve food and help passengers in other ways) as well as the usual ship's crew. The largest cruise ships have casinos, shops, many restaurants, theaters for both live entertainment and movies, several pools, day care, a gym, and a running track. The most expensive cruises often have more crew and staff than passengers. This means that the people who control the cruise can give many personal services.
Today, hundreds of cruise ships sail all over the world. Some carry over 3,000 passengers. These are some of the largest ships ever built. For some places, such as Antarctica, because it lacks other methods of regular transport, cruise ships are one of the few ways for tourists to visit.