The British Broadcasting Corporation (BBC) is a British public service broadcaster. Its headquarters are at Broadcasting House in Westminster, London, and it is the world's oldest national broadcasting organisation and the largest broadcaster in the world by number of employees. It employs over 20,950 staff in total, 16,672 of whom are in public sector broadcasting. The total number of staff is 35,402 when part-time, flexible, and fixed-contract staff are included.
Britain's first live public broadcast from the Marconi factory in Chelmsford took place in June 1920. It was sponsored by the Daily Mail's Lord Northcliffe and featured the famous Australian soprano Dame Nellie Melba. The Melba broadcast caught the people's imagination and marked a turning point in the British public's attitude to radio. However, this public enthusiasm was not shared in official circles where such broadcasts were held to interfere with important military and civil communications. By late 1920, pressure from these quarters and uneasiness among the staff of the licensing authority, the General Post Office (GPO), was sufficient to lead to a ban on further Chelmsford broadcasts.