The British Nationality Act 1981 is a law that redefined British citizenship and established new categories of nationality. It replaced the previous system that allowed individuals from former colonies to automatically become British citizens. Under this act, individuals born in the UK after January 1, 1983, are British citizens only if at least one parent is a British citizen or has settled status. The act also introduced the concept of British Overseas Territories Citizenship and British Dependent Territories Citizenship. These categories apply to individuals connected to the UK's overseas territories. The changes aimed to clarify nationality rights and reflect the changing nature of the British Empire.