Theatre or Theater?
Your choice!
Theatre
Exemple : ‘’I saw an amazing play at the theatre/theater last night.’’
There is a difference in the spelling of the word dependant upon location. In British English the correct spelling is "theatre", however, in American English it is spelt "theater."
Theater
Exemple : ‘’The new theater will open tomorrow.’’
The American spelling of the word has the same meaning as the English. It is fairly common for the American spellings of words which end in "tre" in British English to end in "ter". Another example is the word "centre" which is spelled "center" in American English.