One of the niftiest things on the internet is the Wikipedia. It's a free open source (meaning you can add to and edit information!) encyclopedia. Since it's open source, it's kept up-to-date in real time. Chicago's entry is a nice neat nutshell that gives one a good overview of the city. At a glance it tell you about the history, geography, novels sets in Chicago, companies based here and much, much more. The best part? If you feel it's missing something, just go ahead and add your information. Power, in the hands of the user. Related: What is a Wiki?