Unlike many contries Britain has an unwritten constitution, not being contained in a single legal document. It is based on statutes and important documents, customs and conventions, and can be changed by a simple Act of Parliament like any other law. So Parliament as a legislative body can in theory do whatever it wishes as the separation of powers between the Parliament, Government and Judiciary(law courts) is only theoretical and it´s not clearly divided. Parliamentary sovereignty is the most important part of the UK constitution.
The British system of government is the oldest parliamentary democracy in Europe. British parliament was formed in the eleventh century and, after the signing of the Magna Charta by King John in the year 1215, it came to power and became the main part in the system of government. In this way, England set up the base of democracy in the whole Europe.
Parliament
The British Parliament – like most in the world – is bicameral, i.e. it composes of two chambers: the House of Lords and the House of Commons.
The Commons
Members of the House of Commons are elected by local residents to represent an area of the country in Parliament. So each MP represents one of 650 constituencies (areas)into which UK is divided. They chose their Speaker among themselves. They are paid a salary and the expenses for the sittings. House of the Commons is one of the key places where government ministers, like the Prime Minister and the Chancellor, and the principal figures of the main political parties, work.
General