English in the USA differs considerably from British English. Pronunciation is the most striking difference but there are also a number of differences in vocabulary and spelling as well as slight differences in grammar. On the whole, British people are exposed to a lot of American English on TV, in films and so on and so they will usually understand most American vocabulary.
American spelling is usually simpler. For example, British English words ending in -our and -re, end in -or and -er in American English, e.g. colour/color, centre/center. There are differences in individual words too, e.g. British ‘plough’ becomes ‘plow’. The American spelling usually tries to correspond more closely to pronunciation.
Here are some common US words with their British equivalents.
Here are some words and phrases which can cause confusion when used by Brits and Americans talking together because they mean something different in each ‘language’.