Legislative: parliament (house of lords, commons and the monarch).
Executive: prime minister and cabinet.
Judiciary: supreme court
Constitutional monarch: ceremonial role of the current king.
Parliamentary sovereignty: parliament can make, amend or unmake any law and cannot bind its successor nor be bound by its predecessors.
Conventions: traditions not contained in law but influential in the operation of a political system.
Common law: laws made up by judges in cases where the law does not cover the issue or is unclear.
Rule of law: principle all people and bodies, including government, must follow the law and can be held to account if they do not.
Unentrenched/entrenched: an entrenched constitution requires separate rules and procedures for amendment.
Constitution: set of rules determining where sovereignty lies in a political system.
Unitary/federal: a unitary political system is one where all legal sovereignty is contained in a single place.
Statute law: law passed by parliament.
Authorities work: written by an expert describing how a political system is run; it is not legally binding but is taken as a significant guide.
Treaties: formal agreements with other countries, usually ratified by parliament.
Codified: written in a single, authoritative document that has been agreed on some particular occasion.
Un-codified: made up of a number of different sources.
Devolution: the dispersal of power, but not sovereignty, within a political system.
Quasi-federalism: a system of devolution where it is so unlikely or difficult for power to be returned to central government that it is a federal system.