What? A spirit distilled from a beer, in turn made from fermented cereals (typically malted barley, wheat, corn or rye) and usually matured in an oak cask.
Where? Scotland has most and many of the greatest distilleries, Ireland fell on hard times but is fighting back, and Japan has only a few producers but very high quality. In recent times, smaller craft whisky distilleries are popping up everywhere.
When? The first written records in Scotland are 1494, but both the Scots and Irish were distilling for a long time before that. Before that? China? The Middle East? The monasteries of Europe? There's no firm evidence so lets not pretend there is.
How? We're not snooty about how to serve whisky, but if you are exploring single malt small amounts of water added gradually really helps. Iced whisky is very tasty, and expert Dave Broom even recommends coconut water!
Tip For Beginners: Try not to get confused by regions. Scotch single malt distilleries developed certain flavour styles in particular regions for historical reasons. Islay style malts can be, and are, made in India, Japan and Sweden.