the only relevant part of what Sci said was the bit that went:
the rest was unnecessary, especially since he could've just as easily pointed the guy to the original fucking article on wikipedia.
You have a collection of islands, commonly called the British Isles. This archipelago's name is sometimes objected to by the Irish, who object to it all being called British, but I'm going to use that term for convenience.
The British Isles is comprised of two major islands and lots of tiny little islands. The two big islands are the island of Great Britain, which is to the east, and the island of Ireland, which is to the west.
On the island of Great Britain, there exists England, Scotland, and Wales. On the island of Ireland, there exists Northern Ireland and the Republic of Ireland (whose formal name is just "Ireland," but which I'll call the Republic of Ireland to avoid confusion with the island).
England, Wales, Scotland, and Northern Ireland are all part of a single sovereign state called the United Kingdom of Great Britain and Northern Ireland. The Republic of Ireland used to be part of the United Kingdom
the rest was unnecessary, especially since he could've just as easily pointed the guy to the original fucking article on wikipedia.