Illinois is an state in United States.
An administrative division is a section of a country or other political division which is created and used for the purpose of government. Countries are often divided up into these smaller entities to allow for management and of land and people without having to govern them all as one unit. For example in the United States
, the country is divided into states which are Administrative Divisions. Then within states there are counties which are then broken down into even smaller divisions such as towns, villages or municipalities.