There’s just over 3,000 counties in the United States, which serve as the principal political subdivision of a state. Each state has divided itself into specific political areas known as counties (or as “parishes” in Louisiana and “boroughs” in Alaska). In each county, local officials act as arms of state government, performing many state-related functions, such as administering elections, marriage licenses, and vehicle registration.
In Georgia, counties are the largest general-purpose form of local government. This means that apart from helping administer state government functions, counties can provide a variety of local services to their citizens. In this role, some large urban counties resemble cities in the types of local government services they provide.
Source: GeorgiaInfo
Georgia has 159 counties, second only to Texas, which has 254. No matter where you live in Georgia, you reside in a county.