Chicago is the largest city in the U.S. state of Illinois, as well as the third-most populous city in the United States with a population of 2.8 million.[1] Known as the "Second City," the "Windy City," the "City of Big Shoulders," and "Chi-town" (along with other nicknames and colloquial nicknames that reflect the city's character), Chicago is located along the southwestern shore of Lake Michigan. When combined with its suburbs and nine surrounding counties in Illinois, Wisconsin, and Indiana, the greater metropolitan area known as Chicagoland encompasses a population of 9.3 million, making it the third-largest in the United States.

Chicago is the United States' second financial center with the nation's second largest central business district. The city also has the third largest gross metropolitan product in the nation - approximately $390 billion. Manufacturing (which includes chemicals, metal, machinery, and consumer electronics), printing and publishing, and food processing also play major roles in the city's economy.

Chicago is home to eleven Fortune 500 companies, while the metropolitan area hosts an additional 21 Fortune 500 companies. Chicago also hosts 12 Fortune Global 500 companies and 17 Financial Times 500 companies. The city and its surrounding metropolitan area are also home to the second largest labor pool in the United States with approximately 4.25 million workers.

As of the 2000 census, there were 2,896,016 people, 1,061,928 households, and 632,909 families residing in the city of Chicago proper. The median income for a household in the city was $38,625, and the median income for a family was $42,724. Males had a median income of $35,907 versus $30,536 for females.

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