Originally Posted by
hipquest
This may come across as a very silly question but...
When DH and I travel to a foreign country we try to, at least, know a few phrases of the local language but this will be my first time in London soooo... should I use the terms that Brits use versus my normal American English?
No.
Unless the word is so regional that it's unlikely to be understood. No one will think you're rude for speaking in American English.
The ubiquity of American TV and cinema means most of the Anglophone world understands American English far better than the average American understands non-American English.