British English adds to some words by inserting what Americans would call supererogatory vowels - "aluminium" vs."aluminum," and all the words like "vigour," colour," "labour" etc. Also, British English tends to prefer the French spelling of words like "metre" and its siblings, in contrast with American English opting for the German "meter." Pronunciation is also quite different, most noticeably in "u" Most Americans would say "Noo York," while most speaker of British English, or its derivatives elsewhere, would say "Nyou York." Even the single vowel "u" is often pronounced quite differently - "aloominum" vs "alyouminium." And this doesn't even begin to touch on the variations present in NZ English (my mother tongue), Australian English - note that I am steadfastly resisting the urge to make "oxymoron" type remarks here - and the many other flavours this wondrous tongue has adopted. Please note also, that the above comments are the ravings of a madman, and represent little more than personal opinions of questionable worth.

"Nationalism is an infantile disease, the measles of humanity" - Albert Einstein