Please note that whisky is not called scotch in Scotland. Here it is simply whisky (or commonly refered to as a "nip" of a "dram").

There are many, many different Scottish whiskys, and contrary to what jde says in his writeup Speyside is not the most commonly drank, that title would probably go to Famous Grouse.

From what I have gathered so far there is a much smaller variety (as one would expect) of whiskys available in the U.S. compared to in Scotland itself. This is a deep shame, because I am fond a of a wee dram every so often.