U.S. or U.K.

In 1776, 13 colonies on the Atlantic coast of North America declared their independence from Great Britain. This was followed by a short war in which the United Kingdom lost control of this area.

Noah Webster, an American who lived in the eighteenth and nineteenth centuries, wrote the first "American" dictionary and simplified spelling. He wanted American English to reflect a different culture since the US had become independent. It is simpler than "British", but the UK form (British) is closer to the French language.

In addition, the Present Perfect is used more in UK English than in US English. This makes for a simple and clear "American," but a more nuanced and sophisticated "British." Canadians are moving away from the older British spelling and the simpler American spelling is becoming more common. However, the British is still found in dictionaries as the "Canadian" form. Pronunciation remains the same, since it is only a question of spelling.

In addition, in American English, some verbs are considered regular whereas in Britain and Canada, they are irregular. Often Canadians will use the American form for the Simple Past tense but the British form for an adjective.

E.g. I burned my toast, so now I have burnt toast.

For the forms of the verb get, Americans will say get, got, gotten in their lists of irregular verbs while the British will use get, got, got. Canadians usually follow the American form on this one.