The United Kingdom is a constitutional monarchy with a parliamentary government (officially known as His Majesty’s Government). London is the national capital of the UK (and its largest city) and home to King Charles III, Parliament, the Prime Minister and Cabinet, and the Supreme Court of the United Kingdom.
The Parliament consists of the House of Commons (lower house), the House of Lords (upper house) and includes the Prime Minister and his/her Cabinet of Ministers (e.g., Chancellor of the Exchequer, Secretary of State for Defence, Secretary of State for the Home Office, etc.). British citizens vote in elections to choose Members of Parliament (MPs) to represent them and the political party (either Conservatives or Liberals) that gets a majority of the 650 seats in the House of Commons usually selects the next Prime Minister to form a government (there are other ways in which the Prime Minister may be chosen).
Liz Truss has been the British prime minister since September 2022. In the United Kingdom, the Prime Minister is the Head of Government, but the Monarch is the Head of State. The Prime Minister (PM) serves a unique role as the leader of both the executive and legislative branches of the British Government and along with his/her Cabinet of Ministers, is responsible for running the national government. Number 10 Downing Street in London is the official residence and office for British prime ministers.
Since 8 September 2022, King Charles III has reigned as the Monarch of the United Kingdom, following the death of his mother, Queen Elizabeth II, who reign for over 70 years. His Royal Majesty lives in Buckingham Palace in London (where the famous Changing of the Guard ceremony is held) and has other homes such as Windsor Castle (his country home in England); Holyrood Palace in Scotland; Balmoral Castle (his summer residence in Scotland; Sandringham Estate (his home in England for the winter holidays); and Hillsborough Castle (his official residence in Northern Ireland).
Today, the role of the Monarch is more ceremonial and symbolic (for example, the Monarch’s image is used on British currency; he is the Head of the Commonwealth and King of Australia, King of Canada, King of New Zealand, etc.).
Nonetheless, the Monarch also wields many substantial and unique powers. For example, the Monarch can appoint and dismiss the Prime Minister; the Monarch can dissolve Parliament; His Royal Majesty’s signature is require for bills to become laws; the Monarch is the Head of the British Armed Forces; and he has Royal Prerogatives (e.g., summoning Parliament; making peace; declaring war; issuing passports; regulating the British civil service; dismissing or appointing ministers; negotiating and ratifying international agreements, alliances, and treaties).
Some rather unique powers that King Charles III also has is that he owns all of the unmarked swans that are in the open waters of the United Kingdom; he also owns the dolphins, porpoises, sturgeons and wales in British waters; King Charles III does not require a passport to travel abroad; the Monarch also does not need a driving license or license plates on his cars; King Charles III is immune from prosecution; he can grant a royal pardon to criminals; the Monarch can appoint Lords to the House of Lords (the upper house of Parliament); King Charles III can also appoint knights (for example, Sir Paul McCartney, Sir Elton John, Sir Anthony Hopkins, and Sir Mick Jagger); the Monarch is the Head of the Church of England (“Defender of the Faith”); he has his own cash machine in Buckingham Palace; he has authority to take over any British ship; plus the Monarch does not have to pay taxes.