The Parliament of the United Kingdom is split into three separate parts, the House of Commons (the lower house), the House of Lords (the upper house) and the monarch. Most legislative power is concentrated in the House of Commons. It is made up of 650 members of parliament (MPs). These people are elected by the people of the United Kingdom to represent them in the House of Commons. The leader of the political party who commands a majority of MPs is usually made the prime minister of the United Kingdom, the head of government. The head of state is always the monarch.