The early 20th century marked the beginning of the film industry, with the establishment of Hollywood studios like MGM, Paramount, and Warner Bros. This period, often referred to as the Golden Age of Hollywood, saw the rise of iconic movie stars like Greta Garbo, Clark Gable, and Marilyn Monroe. Classic films like Casablanca (1942), The Wizard of Oz (1939), and Singin' in the Rain (1952) continue to captivate audiences today.