Los Angeles officially the City of Los Angeles and often known by its initials L.A., is the largest city in the U.S. state of California. With an estimated population of nearly four million people, it is the country's second most populous city (after New York City) and the third most populous city in North America (after Mexico City and New York City). Los Angeles is known for its Mediterranean climate, ethnic diversity, Hollywood entertainment industry, and its sprawling metropolis.