The British Isles are an archipelago off the western coast of Europe, consisting of a number of islands; the two largest of which are Great Britain, which is divided between England, Scotland, and Wales, and Ireland, which is divided between Northern Ireland - which is part of the UK - and the Republic of Ireland, an independent state whose name reflects its claim to the whole isle of Ireland. This has led to a naming controversy as The British Isles and Great Britain (and therefore the British) are different things entirely.
There are also thousands of smaller islands in this group; almost all are parts of England, Northern Ireland, the Republic of Ireland, Scotland or Wales. But they also include the British Crown Dependencies of the Isle of Man and the Channel Islands (although the latter are so close to France that they're often not counted as part of the island group, although they are part of the sovereign state that dominates it). The Principality of Sealand is an unrecognised micronation on an artificial island off the coast of England.
Great Britain's name is a translation of the French Grande Bretagne, which has the prefix Grande to differentiate it from Bretagne. But the English name for Bretagne is Brittany.
Due to erosion, drainage of marshes and land reclamation there are a number of places within the archipelago that are called islands but which are no longer surrounded by water.
The archipelago contains four islands called Holy island, one each in England, Ireland, Scotland and Wales.
Confused? Well, you should be.
Articles relating to the British Isles.