What is the Union Jack?
The Union Jack, also called the Union Flag, is the national flag of the United Kingdom. It combines the crosses of St George for England, St Andrew for Scotland and St Patrick for Ireland.
The first version of the flag was created in 1606, after King James VI of Scotland became James I of England, uniting the two crowns. It combined the red cross of St George with the white diagonal cross of St Andrew on a blue background.
The current design was adopted in 1801, when Great Britain united with Ireland. The red diagonal cross of St Patrick was added.
Why Wales is not included
Wales is not represented on the flag because it was already considered part of the Kingdom of England when the first Union Flag was created. Some Welsh people have suggested adding the Welsh dragon.
The name Union Jack is commonly used, although some people say it should be called the Union Jack only when flown at sea. Both names are accepted today.
The flag is not symmetrical, so it can be flown upside down by mistake. The Union Jack also appears in the corner of the flags of Australia, New Zealand and other countries with British history.