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Legislation introduced into the body of law by the apparatus of state (e.g., the Government). In the UK, primary legislation takes the form of statutes, or Acts of Parliament (see: Statute), and Statutory Instruments (SIs), or 'Regulations' (see: Statutory instrument). Not all authorities consider SIs as 'primary', as they are often derived from Acts of Parliament and deal with their interpretation. However, both Statutes and SIs are primary in the sense that they are original, written statements of the law, and distinct from case law (see: ). For a discussion of UK primary legislation, see Statute.