The Federal Reserve Act of 1913 called for a central banking system with a central governing Board and a decentralized operating structure of multiple Reserve Banks. This hybrid structure is still in place today.
The 12 Federal Reserve Banks are the operating arms of the Federal Reserve System. Each Reserve Bank is an independent corporation and operates within its own particular geographic area, or District, of the U.S.
The Board of Governors of the Federal Reserve is a U.S. federal agency that guides the operation of the Federal Reserve System, including overseeing the operations of the 12 Reserve Banks.