Chicago is a major city located on the western shore of Lake Michigan in the Midwestern United States. It serves as the most populous city in the state of Illinois and is the county seat of Cook County, which is the second-most populous county in the country.
As of the 2020 census, Chicago has a population of 2.74 million people, making it the third-most populous city in the United States. The surrounding metropolitan area contains approximately 9.62 million residents and ranks as the third-largest metropolitan area in the nation.