Here are some of the main differences in vocabulary between British and American English. Bear in mind that there can be differences in the choice of specific terms depending on dialect and region within both the USA and the UK.
British English =American English
Lorry = Truck
Barrister=Attorney
Bill=Check
Biscuit=Cookie
Film=Movie
Rubbish=Garbage
Holiday= Vacation
Lift=Elevator
Mad= Crazy
Petrol= Gas
Postcode= Zipcode
Toilet=Restroom
Railway=Railroad
Flat=Apartment
Programme=Show
Landlord= Owner
Football= Soccer