• National Functional Classification Maps in MichiganNational Functional Classification is a transportation planning tool. All public roads are classified according to function -- this allows roads to be studied and compared across different regions of the state or the entire country. National Functional Classification is also used to determine which roads are eligible to receive federal funds (federal-aid) for improvements. National Functional Classification may be abbreviated as NFC. Try the links on this page to find out more or send an e-mail to mdot-nfc@michigan.gov with a specific information request.