Based on the etymology of United Kingdom, it was the name United Kingdom is self-descriptive; the name Britain probably derives from the Celtic word pretani, meaning "painted people;" the designation of Great Britain for England, Scotland, and Wales dates back to medieval times and was used to distinguish the island from Little Britain, or Brittany, in modern France; the name Ireland evolved from the Gaelic name Eriu, which is possibly derived from the Old Celtic iveriu, meaning "good land". The Government system in this country is the parliamentary constitutional monarchy; a Commonwealth realm type and the different Administrative divisions includes: England: 24 two-tier counties, 32 London boroughs and 1 City of London or Greater London, 36 metropolitan districts, 59 unitary authorities (including 4 single-tier counties*)

two-tier counties: Cambridgeshire, Cumbria, Derbyshire, Devon, East Sussex, Essex, Gloucestershire, Hampshire, Hertfordshire, Kent, Lancashire, Leicestershire, Lincolnshire, Norfolk, North Yorkshire, Nottinghamshire, Oxfordshire, Somerset, Staffordshire, Suffolk, Surrey, Warwickshire, West Sussex, Worcestershire

London boroughs and City of London or Greater London: Barking and Dagenham, Barnet, Bexley, Brent, Bromley, Camden, Croydon, Ealing, Enfield, Greenwich, Hackney, Hammersmith and Fulham, Haringey, Harrow, Havering, Hillingdon, Hounslow, Islington, Kensington and Chelsea, Kingston upon Thames, Lambeth, Lewisham, City of London, Merton, Newham, Redbridge, Richmond upon Thames, Southwark, Sutton, Tower Hamlets, Waltham Forest, Wandsworth, Westminster

metropolitan districts: Barnsley, Birmingham, Bolton, Bradford, Bury, Calderdale, Coventry, Doncaster, Dudley, Gateshead, Kirklees, Knowlsey, Leeds, Liverpool, Manchester, Newcastle upon Tyne, North Tyneside, Oldham, Rochdale, Rotherham, Salford, Sandwell, Sefton, Sheffield, Solihull, South Tyneside, St. Helens, Stockport, Sunderland, Tameside, Trafford, Wakefield, Walsall, Wigan, Wirral, Wolverhampton

unitary authorities: Bath and North East Somerset; Bedford; Blackburn with Darwen; Blackpool; Bournemouth, Christchurch and Poole; Bracknell Forest; Brighton and Hove; City of Bristol; Buckinghamshire; Central Bedfordshire; Cheshire East; Cheshire West and Chester; Cornwall; Darlington; Derby; Dorset; Durham County*; East Riding of Yorkshire; Halton; Hartlepool; Herefordshire*; Isle of Wight*; Isles of Scilly; City of Kingston upon Hull; Leicester; Luton; Medway; Middlesbrough; Milton Keynes; North East Lincolnshire; North Lincolnshire; North Northamptonshire; North Somerset; Northumberland*; Nottingham; Peterborough; Plymouth; Portsmouth; Reading; Redcar and Cleveland; Rutland; Shropshire; Slough; South Gloucestershire; Southampton; Southend-on-Sea; Stockton-on-Tees; Stoke-on-Trent; Swindon; Telford and Wrekin; Thurrock; Torbay; Warrington; West Berkshire; West Northamptonshire; Wiltshire; Windsor and Maidenhead; Wokingham; York

Northern Ireland: 5 borough councils, 4 district councils, 2 city councils

borough councils: Antrim and Newtownabbey; Ards and North Down; Armagh City, Banbridge, and Craigavon; Causeway Coast and Glens; Mid and East Antrim

district councils: Derry City and Strabane; Fermanagh and Omagh; Mid Ulster; Newry, Murne, and Down city councils: Belfast; Lisburn and Castlereagh

Scotland: 32 council areas

council areas: Aberdeen City, Aberdeenshire, Angus, Argyll and Bute, Clackmannanshire, Dumfries and Galloway, Dundee City, East Ayrshire, East Dunbartonshire, East Lothian, East Renfrewshire, City of Edinburgh, Eilean Siar (Western Isles), Falkirk, Fife, Glasgow City, Highland, Inverclyde, Midlothian, Moray, North Ayrshire, North Lanarkshire, Orkney Islands, Perth and Kinross, Renfrewshire, Shetland Islands, South Ayrshire, South Lanarkshire, Stirling, The Scottish Borders, West Dunbartonshire, West Lothian

Wales: 22 unitary authorities

unitary authorities: Blaenau Gwent, Bridgend, Caerphilly, Cardiff, Carmarthenshire, Ceredigion, Conwy, Denbighshire, Flintshire, Gwynedd, Isle of Anglesey, Merthyr Tydfil, Monmouthshire, Neath Port Talbot, Newport, Pembrokeshire, Powys, Rhondda Cynon Taff, Swansea, The Vale of Glamorgan, Torfaen, Wrexham