United Kingdom legislation

Legislation in the United Kingdom comes from a number of different sources:

Actss of the United Kingdom Parliament
statutory instruments (orders and regulations) made by a Minister or by the Queen in Council, generally subject either to parliamentary approval (affirmative procedure) or parliamentary dissallowance; these are made either under Acts or by the royal prerogative.
Acts of the devolved Scottish Parliament, and statutory instruments made by the Scottish Executive (likewise subject to approval or disallowance by the Scottish Parliament)
Statutory instruments made by the National Assembly for Wales
Acts of the Northern Ireland Assembly, and statutory instruments made by Northern Ireland Departments
Decisions, directives and regulations of the European Communities.