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Music，film and television，as well as books and magazines，are common sources of entertainment in the United States;and constitute an important part of the popular culture.Messages conveyed in these forms of entertainment have a strong influence on Americans in their personal choices and political actions.
Music is an important part of American life.Americans use music，especially popular music，to convey cultural and social information，and to express emotions.Popular music is often regarded as a symbol of youthful rebellion against social conventions.Such music often takes the form of commercial products catering to a mass audience.Types of American popular music include rock jazz and country music.
Rock is a form of popular music marked by a strong steady beat and rhythmic melodies.Rock evolved from a form of black music known as rhythm and blues;the new music，originally called“rock and roll”，appealed to white teenagers and soon became very popular in the United States.It has since evolved into a variety of different forms and spread across the world.
Jazz is perhaps America’s most unique contribution to music.It originated in New Orleans in the early 20th century from traditional African⁃American musical forms，blending influences from folk music，church music，and work chants，and using rhythms of African music and European forms of harmony and melody.One of jazz’s main distinguishing features is its emphasis on improvisation，in which musicians invent music in the same moment as they are playing it.Jazz is also notable for the broad diversity of its stylistic forms.
Country music originated from folk songs brought to America by English，Scottish and Irish immigrants who settled in the southeastern United States.Marked by a melancholy rhythmic sound，country music，from the beginning，was associated with struggle and determination.It praised hard work and good fun，and told tales of romantic love and achievements，and as well as addressing everyday problems（often shared by the audience）and troubling issues of the time.Because of its simplicity and its role as a reflection of a significant part of society，country music remains an important form of American cultural expression.
Americans watch movies although home viewing has diverted a large part of the audience away from movie theaters.Movies typically carry much cultural information，so they have an impact on the audience.In order to protect children from scenes of violence and other unwanted influences in movies，and also to protect movie producers themselves from public criticism，the Motion Picture Association of America administers a voluntary rating system for movies shown in U.S.theaters.The system rates all movies according to one of five categories：G，PG，PG⁃13，R，and NC⁃17.“G”stands for“general audience”meaning that a movie is suitable for everyone.“PG”stands for“parental guidance”，and indicates that some materials in a movie may not be suitable for children.“PG⁃13”means that some of a movie’s content may not be appropriate for children under 13 and parents are strongly cautioned.“R”stands for“restricted，”meaning a child younger than 17 must be accompanied by a parent or adult guardian when watching the movie.“NC⁃17”means that no one of 17 years old or younger is allowed to see the movie.
With the development of television in the mid⁃20th century，people began to spend more time watching TV programs at home instead of going to the cinema.Many blame TV programs for showing too much violence.Television is also a fast and reliable way to deliver messages to the public.The federal and state governments often use television to communicate their policies.Critics argue that many TV programs also indoctrinate the audience with nationalist and patriotic themes and messages，especially during times of crisis.
The major television networks include Fox，NBC（the National Broadcasting Company），CBS（the Columbia Broadcasting System），ABC（the American Broadcasting Company），CNN（Cable News Network）and the CW Television Network.These networks are mainly supported by commercials and cable television subscription fees.PBS（the Public Broadcasting System）is supported by federal funding and donations，and does not carry commercials.Compared to the commercial networks，a large share of the programs shown on PBS are educational and informational，or show cultural events such as plays and concerts.
Many Americans still love to visit museums，which can be found in most cities.Books also remain popular，and most communities have a public library.The main library in the United States is the Library of Congress in Washington D.C.