The oldest of the British armed services, the Royal Navy is therefore known as the 'Senior Service'. It forms a constituent part of the Naval Service, which also comprises Royal Marines, Royal Fleet Auxiliary, Royal Naval Reserve and Royal Marines Reserve.
The head of the Royal Navy is the Lord High Admiral, a position that has been held by the Sovereign since 1964.
The professional head of the Naval service is the First Sea Lord, and the upper echelons of Naval Command are the members of the Admiralty Board, comprising the First Sea Lord, Commander in Chief Fleet, Second Sea Lord, Commander in Chief Naval Home Command, Naval Member for Logistics, Controller of the Navy, Assistant Chief of Naval Staff.
Fleet command of all deployable fleets is the responsibility of Commander-in-Chief Fleet, with headquarters at HMS Excellent, Portsmouth and Operational Headquarters at Northwood, Middlesex.
The Naval hierarchy is arranged in distinct groups
|Flag Rank Officers||Admiral of the Fleet*, Admiral (also referred to as a 'Full-Admiral'), Vice Admiral, Rear Admiral, Commodore|
|Commissioned Officers||Captain, Commander, Lieutenant-Commander, Lieutenant, Sub-Lieutenant, Midshipman|
|Warrant Officers||Senior Rates (Non-commissioned officers), holding a Royal Warrant. Addressed as 'Mr. (surname)' or 'Warrant'. Full title includes their specialism, for example: 'Warrant Officer (Catering Services) Jones'. Abbreviated to WO.|
|Senior Rates||Comprising Chief Petty Officers and Petty Officers, (CPO and PO). Addressed as 'Chief', and 'PO' (surname). Similarly, their full title includes their specialism.|
|Junior Rates||Comprising Leading Hands and Able Seamen. Addressed as 'Leader', or 'Killick', and 'AB', respectively**, followed by their specialism and surname.|
*In the 1990s this rank was abolished, and only those who held the rank prior to its abolition remain using the rank.
**For guidance on the etymology of these forms of address, click the following link: Navy slang
'Royal Navy' or 'RN'
All officers of the Royal Navy below the rank of Rear Admiral, whether on the active or retired lists, are entitled to the words 'Royal Navy' or 'RN' after their name, preceded by decorations, etc. 'RN' is generally used where the rank is abbreviated, 'Royal Navy' is used when the rank is written in full.