While many people use the terms ​United Kingdom, Great Britain, and England interchangeably, there is a difference between them—one is a country, the second is an island, and the third is a part of an island.

The United Kingdom

The United Kingdom is an independent country off the northwestern coast of Europe. It consists of the entire island of Great Britain and a northern part of the island of Ireland. In fact, the official name of the country is the "United Kingdom of Great Britain and Northern Ireland."

The capital city of the United Kingdom is London and the head of state is currently Queen Elizabeth II. The United Kingdom is one of the founding members of the United Nations and sits on the United Nations Security Council.

The creation of the United Kingdom heralds back to 1801 when the unification between the Kingdom of Great Britain and the Kingdom of Ireland led to the establishment of the United Kingdom of Great Britain and Ireland. When southern Ireland gained independence in the 1920s, the name of the modern country then became the United Kingdom of Great Britain and Northern Ireland.

Great Britain

Great Britain is the name of the island northwest of France and east of Ireland. Much of the United Kingdom consists of the island of Great Britain. On the large island of Great Britain, there are three somewhat autonomous regions: England, Wales, and Scotland.

Great Britain is the ninth largest island on Earth and has an area of 80,823 square miles (209,331 square kilometers). England occupies the southeast portion of the island of Great Britain, Wales is in the southwest, and Scotland is in the north. Scotland and Wales are not independent countries but do have some discretion from the United Kingdom with respect to internal governance.

England

England is located in the southern part of the island of Great Britain, which is part of the country of the United Kingdom. The United Kingdom includes the administrative regions of England, Wales, Scotland, and Northern Ireland. Each region varies in its level of autonomy but all part of the United Kingdom.

While England has traditionally been thought of as the heart of the United Kingdom, some use the term "England" to refer to the entire country, however, this is not correct. While it's common to hear or see the term "London, England," technically this is also incorrect, as it implies that London is the capital of England alone, rather than the capital of the entire United Kingdom.

Ireland

A final note on Ireland. The northern one-sixth of the island of Ireland is the administrative region of the United Kingdom known as Northern Ireland. The remaining southern five-sixths of the island of Ireland is the independent country known as the Republic of Ireland (Eire).

Using the Right Term

It is inappropriate to refer to the United Kingdom as Great Britain or England; one should be specific about toponyms (place names) and utilize the correct nomenclature. Remember, United Kingdom (or the U.K.) is the country, Great Britain is the island, and England is one of the U.K.'s four administrative regions.

Since unification, the Union Jack flag has combined elements of England, Scotland, and Ireland (although Wales is omitted) to represent the unification of constituent parts of the United Kingdom of Great Britain and Northern Ireland.