The above map shows the difference between British Isles, Great Britain, United Kingdom, and England. Although terms often used interchangeably, they actually mean different things.
The British Isles: while it is the most common name for the archipelago, it is not used in the Republic of Ireland, who instead refer to them as either British-Irish Isles of simply as these islands.
The names you choose include islands of Great Britain, Ireland and six thousand small isles (including Bailiwicks of Jersey and Guernsey and Isle of Man). In total, it covers an area of 315,159 km (121,684 square meters) and is a population of more than 67 million people.
Great Britain:
Is the larger of two main islands in the British Isles accounting 73 percent of the land (229,848 km², 88,744 square meters) and 90% of the population (60.8 million) in the British island. It is divided into three countries, all of which are part of United Kingdom(see below).
England is the UK’s largest country accounting for 57% (130,279 km 2, 50,301 square meters) and 86% population (53 million).
Scotland holds 34% of the second largest country accounting (77,933 km 2, 30,090 square meters) and 9 percent population (5.3 million)
Wales 9% of the smallest country accounting in the UK (20,779 km, 8,022 square meters) and 5 percent population (3 million)
Ireland:
It is smaller than two large islands in the archipelago, which is 27% of the area (84,421 km 2, 32,5 9 square square meters) of the earth, but only 10% (6.4 million) of the total population. It is divided between Ireland and Northern Ireland’s fully independent autonomous state, which is one of the four countries in the United Kingdom (see below)
Republic of Ireland: 83% of Ireland accounts (70,273 km, 27,133 square meters) and 72 percent population (4.6 million).
Northern Ireland: Only 17 percent of the area (14,130 km, 5,456 square meters) and 28 percent population (1.8 million) accounts.
UK: The UK is the fully independent autonomous states made up of 3 countries on Great Britain and Northern Ireland, which its full name appears: the United Kingdom of Great Britain and Northern Ireland.
Now for fun: England, Scotland, and Wales are all British, but not people from Northern Ireland who are Irish (despite also being UK citizens). People from the Republic of Ireland are just Irish. And, none of these groups, except for people from England, should be referred to as English.
if that doesn’t fully make sense, Watch this video for more clarification: