Parliament's two Houses, Royal Assent and the United Kingdom Supreme Court

Background

Parliament is separate from the government. It is made up of the House of Commons and the House of Lords, and its role is to look at what the government is doing, to debate issues and pass new laws, and to set taxes.
Ministers are chosen by the Prime Minister from the members of the House of Commons and House of Lords, and are responsible for the actions, successes and failures of their departments.
An Act of Parliament creates a new law or changes an existing law. It is a Bill that has been approved by both the House of Commons and the House of Lords and been given Royal Assent by the Monarch; taken together, Acts of Parliament make up what is known as Statute Law in the UK.
Where an Act does not fix its own start date, commencement can be left to the Secretary of State and the Act is then brought into force by a Statutory Instrument called a Commencement Order or Commencement Regulation.
Certain instruments made under the royal prerogative are called Orders in Council when made by the King on the advice of the Privy Council, and Orders of Council when made by the Lords of the Privy Council without the King's approval.
The Supreme Court of the United Kingdom was established by the Constitutional Reform Act 2005 and opened its doors in October 2009, replacing the Appellate Committee of the House of Lords, whose judges were known as Law Lords.
It hears appeals on arguable points of law of the greatest public importance, for the whole of the United Kingdom in civil cases and for England, Wales and Northern Ireland in criminal cases, and in most cases it sits above all three legal systems as the final court of appeal; it sits in the former Middlesex Guildhall, on the western side of Parliament Square. The United Kingdom has no single unified legal system: there is one for England and Wales, another for Scotland and a third for Northern Ireland.
No UK court, including the Supreme Court, has the power to "strike down" legislation if it is incompatible with the European Convention on Human Rights; it can instead issue a "declaration of incompatibility" inviting legislators to change the law.