Fun British food facts! I personally disagree with the sandwich one (yes, it's named for the Earl of Sandwich, but I'm sure someone else would have come up with the idea sooner), but this is neat nonetheless.
Great Britain is the official name given to the two kingdoms of England and Scotland, and the principality of Wales. The United Kingdom (UK) includes these areas as well as Northern Ireland. Britain refers to only England and Wales, though some will shorten Great Britain with this term.