I am Canadian, so I use colour and favourite (and favour, honour, valour, neighbour etc.), but an American would usually use color and favorite.

Keeping the “u” is usually considered a British thing, so you’re likely to see it used by anyone from the UK or any current or former commonwealth of the UK (Canada, Australia, etc).

I think.

but if u want to know why then im not suree

Brits keep the U

British English: colour and favourite

both spellings are Proper, you just should use them according to which country you’re in 🙂

other differences in spelling–both spellings are Proper too:

American: advertize, behavior, spelled, favor, organize, etc.

British: advertise, behaviour, spelt, favour, organise, etc.

understand better? 🙂 it’s just American and British English, both are Proper English and both are correctly spelled too 😀

others are British