Politics of the United Kingdom
The UK Parliament is the supreme legislative body in the United Kingdom (i.e., there is parliamentary sovereignty), and Government is drawn from and answerable to it. Parliament is bicameral, consisting of the House of Commons and the House of Lords. There is also a devolved Scottish Parliament and devolved Assemblies in Wales and Northern Ireland, with varying degrees of legislative authority.
Westminster system
The Westminster system is a parliamentary system of government developed in the United Kingdom. This term comes from the Palace of Westminster, the seat of the British Parliament.
The system is a series of procedures for operating a legislature. It is used, or was once used, in the national legislatures and subnational legislatures of most former British Empire colonies upon gaining responsible government, beginning with the first of the Canadian provinces in 1848 and the six Australian colonies between 1855 and 1890. However, some former colonies have since adopted either the presidential system (Nigeria for example) or a hybrid system (like South Africa) as their form of government.