Technological innovation and rapid cultural change marked the first few decades of the 20th century in the United States, and California was no exception. Advances in technology led to rapid industrialization of the workplace. Factories and assembly lines became the norm, changing the way Americans worked. As people continued to migrate to California from other parts of the country and around the world in search of work and a better life, the state grew more diverse. With factories producing greater quantities of products, a need emerged for a better way to promote those products to more people, sparking the beginning of the modern advertising industry. Technological innovations and improved communications also influenced popular culture and the way people spent their free time. The movie industry in particular put Southern California on the map, making the area a magnet for would-be stars and star-gazers.