Vendors are companies and other entities who have a right to enter into contracts with the City. All of these vendors are taken from the Vendor, Contract, and Payment Search lookup tool maintained by the Department of Procurement Services. Probably the best way to find vendors is to use the search box in the upper right. Type in any word and you'll get a set of related vendors and contracts. Keep in mind that this is by no means every entity that gets money from the City of Chicago. See more information on this subject here.