Part 1: American English vs British English spelling

often end in '–re' in British English.

For example: 'I live in the center of town.'

changes to 'centre'.

Normally, verbs which end in '–ize' in American English

can be spelt in British English with either '–ize' or '–ise'.

For example: 'Can you organize the meeting?',

changes to 'organise' (or 'organize').

Sometimes words with '–or' in American English

can be spelt in British English using '–our'.

For example: 'What's your favorite color?'

changes to 'favourite' 'colour'.

It doesn't matter whether you use

American English or British English spelling.

Just make sure you use one or the other.