The Italian-American Mafia, often referred to as the Cosa Nostra, is a criminal organization that originated in Italy and became prominent in the United States during the late 19th and early 20th centuries. It is known for its involvement in various illegal activities, including extortion, racketeering, and organized crime. The Mafia operates through a hierarchical structure, with families controlling specific territories and engaging in both legitimate and illegitimate businesses. The Mafia's influence peaked in the mid-20th century, particularly in cities like New York, Chicago, and Philadelphia. Law enforcement efforts, including the use of the RICO Act, have significantly weakened the organization over the years. Despite this, the Italian-American Mafia remains a notable part of American criminal history and popular culture, often depicted in films and literature.