Explain in short (1-4 sentences) the difference between great britain and the uk. in other words, what do we call great britain and what is known as the uk?

In the UK is besides other lands england, scotland, irladniya, some type Malvinas Islands
England is only part of the British Isles
England is a country, United Kingdom - a kingdom.
Britain = England + Scotland + Wales ..
In the United Kingdom of Great Britain and Northern Ireland - England one of the areas