Harry Potter and the Sorcerer's Stone vs. Harry Potter and the Philosopher's Stone?

Alright. I have the whole Harry Potter book series. But the first book (Harry Potter and the Sorcerer's Stone) got ruined today :( Anyway, I'm on Amazon looking for a replacement. And I remembered that my English teacher said that she has the original British version (Harry Potter and the Philosopher's Stone) and I was wondering what the difference is. Is it just the titles, or are the books written slightly different (Ex. edited or unedited) Thanks!