Chicago is similar to New York in that all the condos are like apartments; however, it is different in that condo ownership in Chicago is where owners own the property, common areas and buildings together. They have title to the inside of the unit where they live.
There are many styles of condos in Chicago. The two most recognized is an apartment, and includes two, three, and four-flat walk-ups, mid-level and high-rises, penthouses (which usually include roof-top decks and/or multiple levels), duplexes, and lofts. Townhouses are next and are multi-level properties with full basement. Many are row houses with a small yard in the back.
One type of condo style living in Chicago is hotel living, and is either "owner-use", where the hotel rents out the unit to a guest, or "private-use", where they are not rented and usually away from the rest of the hotel.
In these living/owning agreements, individual units, owned by residents, are maintained by the owner, common areas are taken care of by a homeowners' association.
Check with Chicago Condo, your local real estate company, or check online at any of the real estate site that list the MLS (Multiple Listing Service).
http://www.chicago.condo.com/