Ocean liner

Ocean liner is the name given to (usually large) ships that are used to transport people or goods. These ships travel along given routes; they usually have a schedule. Usually, ocean liners travel long distances. The ships used for short distances, for example across a channel, a lake, or between an island and the coast close by, are called ferries. Ocean liners are used for transportation. Cruise ships are different, they are used for pleasure. 
The “golden Age” of the ocean liner was the first half of the 20th Century, when ocean liners commonly carried hundreds upon thousands of poor immigrants from Europe to North America, the United States especially. Hundreds of ocean liners were built during this period. 
When WW2 started in 1939, many ocean liners were turned into troop ships, to transport soldiers to Europe and Asia, by both sides. After the war, most remaining ocean liners were returned to their original owners. 
In the second half of the 20th century, ocean liners have been replaced by aircraft more and more. In the 1950’s, as airplanes like the De Havilland Comet and Boeing 707 were built, ocean liners seemed redundant as jet liners were faster and easier to build than ocean liners. By the 1980’s, most ocean liners had been retired with only a few outliers staying in service.