Los Angeles is the most populous city in California and the second most populous in the United States, after New York City, with a population of 3.8 million, on a land area of 498.3 square miles (1,290.6 km Los Angeles is also the seat of Los Angeles County, the most populated and one of the most multicultural counties in the United States. The city's inhabitants are referred to as "Angelenos" (/ændʒɨˈliːnoʊz/).

Often known by its initials, LA, and nicknamed the City of Angels, Los Angeles is a world center of business, international trade, entertainment, culture, media, fashion, science, technology, and education. It is home to renowned institutions covering a broad range of professional and cultural fields, and is one of the most substantial economic engines within the United States. Los Angeles has been ranked the third richest city and fifth most powerful and influential city in the world, behind only New York City in the United States. The Los Angeles combined statistical area (CSA) has a gross metropolitan product (GMP) of $831 billion (as of 2008), making it the third largest economic center in the world, after the Greater Tokyo Area and the New York metropolitan area. As the home base of Hollywood, it is known as the "Entertainment Capital of the World", leading the world in the creation of motion pictures, television production, video games, and recorded music. The importance of the entertainment business to the city has led many celebrities to call Los Angeles and its surrounding suburbs home. Los Angeles hosted the 1932 and 1984 Summer Olympics. Los Angeles is also home to renowned universities such as the University of Southern California and the University of California, Los Angeles.