There are two main types of legislation: primary and secondary (or delegated). Secondary legislation is made under the authority of a piece of primary legislation. Examples of primary legislation are: Acts of Parliament; Acts of the pre-UK parliament (acts by independent parliaments of the separate countries prior to unification in 1801); Acts of the devolved parliaments; Church of England Measures; and Prerogative Instruments. Examples of secondary legislation are: statutory instruments made under Acts of Parliament (orders, rules, and regulations); Scottish and Welsh statutory instruments; statutory rules of Northern Ireland; Church instruments; and bye-laws.[i]
Although secondary legislation is often referred to as a statutory instrument, primary legislation may also be referred to as statutes. This distinction is important for purposes of understanding the law in the UK, and it is also important in the Bluebook as there are different citation forms for “Statutes” meaning primary legislation and “Regulations” meaning secondary legislation.
Guides to UK Legislation
Compilations of UK Legislation
The United Kingdom National Archives hosts a web site that is the Official Home of UK Legislation. It has "newly enacted legislation for the UK, Scotland, Wales and Northern Ireland". It also has archives of older legislation, including Acts of the English Parliament going back to 1267, Acts of the Old Scottish Parliament back to 1424, and Acts of the Old Irish Parliament back to 1495. Realize that the legislative process and legislative resources in the UK are very different from what we are used to here in the United States. The National Archives also provides a Guide to Revised Legislation (PDF download) that can help you understand how statutory law is made and promulgated in the UK.