Generally this can refer to any policy-making body leading some institution.
Often though this refers specifically to a group of seven men that head the Federal Reserve Bank. Created on December 23, 1913 by an act of the US Congress this group is often said to wield more power than the President of the United States does. They are ultimately responsible for setting US banking policy and rules. In addition they have several tools they can use to push interests rates and the supply of currency up or down to modify the economy.
Each member is appointed by the President and confirmed by the Senate to serve 14-year terms of office. Members may serve only one full term, but a member who has been appointed to complete an unexpired term may be reappointed to a full term. The President designates, and the Senate confirms, two members of the Board to be Chairman and Vice Chairman, for four-year terms. Currently Dr. Alan Greenspan is Chairman of the Federal Reserve. Vacancies on the BOG occur in every even year giving a President a chance to appoint 2-4 members of the board during his term in office.
By law only one member of the board can come from any of the twelve Federal Reserve Districts. Anyone can be appointed to the BOG but generally nominees are either economists involved with government policy, District Bank Presidents, or in a few cases leaders of industry.
The powers of the Board of Governors include open market transactions (as part of the Federal Open Market Committee), setting regulatory and supervisory responsibilities over banks that are members of the System, bank holding companies, international banking facilities in the United States, Edge Act and agreement corporations, foreign activities of member banks, the U.S. activities of foreign-owned banks, and setting the margin requirements for the purchase of securities such as stocks.
It shares responsibility for the setting of the discount interest rate, and partially the overall interest rate in the US, with the individual District Banks.