God invented whiskey to keep the Irish from conquering the world.
This process of aging, as the components soak into the wood in the heat and return as the product cools down, provides the much of the color that we see in the finished product. In this process however, some 2% per year is lost through evaporation. This is called the "Angels Share" and is accepted by the distiller (sometimes grudgingly). What it means though, is that the longer the product ages, the more that is lost through evaporation. Hence the price difference between a 10-year old, 12-year old, and 25-year old product. Some rare whiskeys are aged for up to 58 years, and are priced accordingly (Johnnie Walker Blue for example). But enough of the technical details, let's talk a little bit about the whiskeys themselves.
There are a number of different versions of the standards, Jameson and Bushmills, each having to do with whether they are a blended or single-barrel whiskey, and the amount of time that they are aged in the barrel. There are additionally, a number other varieties that are well worth indulging in: Paddy, Powers, Tullamore Dew, Red Breast, and Michael Collins. Then there is that rarest and most expensive of Irish Whiskey, Middleton's Very Rare (which amazingly enough is a blended whiskey). This "nectar of the gods" is actually dated by the by the year that it is bottled (with the blend being reformulated every year), and is called very rare because of the small quantities in which it is produced. Irish whiskeys tend to be a little "sweeter" or "lighter" than their counterparts, and may be the easiest on the untried palate.
Serving suggestions:Amazingly enough, even the distillers recommend adding a little water to their product. This "splash" of water opens up the flavors of the whiskey and helps to bring out its complexity. For those of us in the US who seem unable to enjoy a cocktail without ice, I recommend placing a couple of ice cubes (not to be mistaken for loading the glass to the rim) to perform the same function. Many purists (myself included) simply ask for a little water on the side, to allow us to decide what is enough.
In the end, like wine, the best whiskeys are the ones you enjoy. Wade in gently and venture into deeper water when you feel you are ready and I think that you will soon find much to earn your interest. Do not be intimidated by the variety and feel free to take on the more expensive ones when you have learned to appreciate their less expensive counterparts.