So why the differences between British English and American English spelling? Well, British English spelling is heavily influenced by the languages that words were borrowed from: generally French & German. American English spelling is, for the most part, based on how the word sounds when spoken.
English was introduced to North America by the British settlers in the 17th Century and has evolved with every wave of immigration since. The first dictionary of American English was compiled by Noah Webster in 1806 and records the American spelling of words such as harbor instead of harbour. A later edition printed in 1828 already contained over 70,000 words.
As we have already seen in the example of harbor/harbour, one of the most common differences between American and British spelling is the change from -our to -or. Here are some more examples :
British
arbour
ardour
armour
behaviour
clamour
colour
dolour
favour
flavour
harbour
humour
labour
neighbour
odour
parlour
rumour
saviour
American
arbor
ardor
armor
behavior
clamor
color
dolor
favor
flavor
harbor
humor
labor
neighbor
odor
parlor
rumor
savior
If I’ve left any out please write in the comments below :)))
Verbs in British English that end with -ise are always end with -ize in American English. Here are just a few examples to the rule:
British
apologise
organise
recognise
American
apologize
organize
recognize
Another common variation is with verbs that end in –yse in British English which are always spelled –yze in American English:
British
analyse
breathalyse
paralyse
American
analyze
breathalyze
paralyze