As in a previous article where I discussed what is Great Britain, or the UK, (click to read), so the British flag is made-up of parts, three.
The United Kingdom of Great Britain and Northern Ireland, consists of four (4) countries, being,
The three flags of Scotland, England and Northern Ireland are overladed to produce the Union Jack. The Welsh national flag not part of the Union Jack. It was first used in 1801 after the Union of Ireland and Great Britain.
The Flag must be flown the correct way as shown here with the flag pole on the left (note white bands):-
Flag pole correct way incorrect way
The term “Union Jack” could be derived from the small flag that flies from the bow of a ship, on a flag pole called the Jack Staff.
The flag has been called the Union Flag, and todays common usage uses Union Flag.