Los Angeles, officially the City of Los Angeles, often known by its initials L.A., is a major city in California's Southern California region, approximately 342 miles (551 km) south of San Francisco. With a population of 3,792,621 as of 2010, Los Angeles is the second-largest city in the United States, after New York City, and the most populous city in California. Los Angeles is known for its mediterranean climate, ethnic diversity, celebrity culture, traffic, and the film and television industry.