English is a global language but its vocabulary, spelling, and grammar varies around the world. This page is a first effort at tallying up the differences between English vocabulary as it is known throughout the English-speaking world. The most frequently known differences for people in the United States of America are between British and American English: Two countries divided by a common language. However, there are additional differences less well known to speakers of American English between American English and Australian English, Caribbean English, Canadian English, Indian (Asia) English, Irish English, New Zealand English, Scottish English, South African English, etc. Hopefully, with time we can get through them all to portray the astounding variety of ways a common language is used everywhere.
American-British English How to find the British Equivalent for an American Word or Phrase
British-American English How to find the American Equivalent for a British Word or Phrase
NML had a presentation on World Englishes, which you can see here: