When discussing rye whiskey, it can often be confused with Canadian whisky, which is sometimes also called "rye" and sometimes even labeled as such, even though it rarely has much rye in it. For our purposes (and hopefully yours as well) any time we refer to rye whiskey, we are refering specifically to the American Product. The rules for American rye whiskey are essentially the same as for bourbon, with the key differentiation being that rye must be made from mostly rye (51% or more). This produces a fairly distinctive sharp spice component. If you think of the difference in flavor between rye bread and corn bread, you sort of have the idea of the character differences between rye and bourbon (although its not that pronounced).