The British Broadcasting Corporation (BBC) is a British public service broadcasting corporation. Its main responsibility is to provide impartial public service broadcasting in the United Kingdom, the Channel Islands, and the Isle of Man. It is the largest broadcaster in the world by number of employees, with about 23,000 staff. The BBC is headquartered at Broadcasting House in London and has major production centres in Belfast, Birmingham, Bristol, Cardiff, Glasgow, London and Salford and smaller production centres throughout the UK.