Britain is a constitutional monarchy. That means it is a country governed by a king or a queen who accepts the advice of a parliament. It is also a parliamentary democracy. That is, it is a country whose government is controlled by a parliament which has been elected by the people.
The Parliament The British Parliament is divided into two "houses", and its members belong to one or other of them, although only members of the Commons are normally known as MPs (Member of Parliament). The Commons is by far the more important of the two houses.