The politics of Canada function within a framework of parliamentary democracy and a federal system of parliamentary government with strong democratic traditions. Canada is a constitutional monarchy, in which the monarch is head of state. In practice, the executive powers are directed by the Cabinet, a committee of ministers of the Crown responsible to the elected House of Commons of Canada and chosen and headed by the Prime Minister of Canada.

Canada has evolved variations: party discipline in Canada is stronger than in the United Kingdom, and more parliamentary votes are considered motions of confidence, which tends to diminish the role of non-Cabinet members of parliament (MPs). Such members, in the government caucus, and junior or lower-profile members of opposition caucuses, are known as backbenchers. Backbenchers can, however, exert their influence by sitting in parliamentary committees, like the Public Accounts Committee or the National Defence Committee.

Source: Wikipedia