Japanese whisky is modelled from Scotch Whisky - double distilling, malted and/or peated barley, before it’s aged in wood barrels. As opposed to the sweeter American bourbons and ryes, they tend to be drier, smokier, and peatier, and come as single malts or blends. Most of the major distilleries in Japan actually import most of their ingredients from Scotland, using malted and sometimes even peated barley from the Isles. Some distillers use imported bourbon barrels, but others make theirs out of mizunara, a tree only found in Japan that adds its own distinct flavor.
Although it’s becoming increasingly popular, availability outwith Japan is still limited. So if you get the chance, why not try something that's a bit different.