Whisky, or Whiskey, is made from any grain. It must be aged for at least 3 years in a barrel. Scotch, Bourbon, Rye and many others are subsections of the general class called Whisky. Scotch is a whisky made in Scotland. Bourbon is a whisky made with more than 50% corn used in the mash. Canadian Whisky or Rye Whisky has some rye added for flavour. There is an International Spirit Naming Act that many countries have 'signed on' for. It is my understanding that the US has not signed on. Therefore, bourbon is not an internationally protected name, but has been protected by some jurisdictions.