I learned about 2.5D, or two and a half dimensions, from my engineering days. Turns out it’s really quite common to make 2.5D things because, for example, it’s easy to drill or mill down into something, and a pain to turn something on it’s side and drill from the other side. Or, as with vacuum forming it’s easy to suck plastic onto a mould, but a pain to get it off if you’ve got any overhangs as you can’t lift it straight up again. Hence the plastic sandpit in our garden is a 2.5D object rather than true 3D. Civilisation in general looks rather 2.5D from the air as we tend to build up, but don’t find overhangs that easy or practical eg the pyramids.

2.5D

This is generally the source of much confusion. Even amongst those who live over here. If you look carefully at the description of the United Kingdom you’ll see it’s the United Kingdom of Great Britain and Northern Ireland. And the British Isles is the group of islands as a whole including all of Ireland too.

The source I liked best for this explaining this and much more, was Project Britain.

For much further confusion, think for a moment why there’s a UK passport, Great Britain in the Olympic games, and in football we compete as England, Wales, Scotland and N. Ireland separately. 🤔

Great Britain, the United Kingdom and the British Isles: what’s the difference?

The union jack flag is made up of the Saltire of St Andrew for Scotland, and St Patrick for Ireland — a saltire is the heraldic name for the diagonal cross-look — together with the cross of St George for the Kingdom of England. As Wales was a principality at the time the flag was created, not a kingdom, it is not represented in the design.

Before Ireland’s emblem was added there was actually an earlier flag back in 1606— the original union flag — with just Scotland and England present.

The Union Jack