Controversy persists about the UK’s national flag.
Should it we call it the Union Flag or the Union Jack?
The general public uses Union Jack almost universally.
However, some believe that Union Flag is correct term and that Union Jack refers only to the flag when flown from the jack-staff in the bows of a Royal Naval vessel (or at least to its use at sea).
The origins and relationships of the terms ‘Union Flag’ and ‘Union Jack are far from clear.
Discussion on the matter is almost as old as the flag itself.
It is a ubiquitous pub quiz question, and regularly generates enormous postbags at the BBC and other media organisations.
Nonetheless there has existed until now no definitive statement on the correct name,
In his final piece of vexillological research before his death in 2013, David Lister, a founding member of Flag Institute, examined the question in detail.
The Flag Institute, in association with the UK Parliamentary Flags and Heraldry Committee, is now proud to publish the most complete answer ever produced.
https://www.flaginstitute.org/wp/wp-content/uploads/2021/01/Union-Jack-or-Union-Flag.pdf
