The term whisky comes from the Gaelic uisgebeatha – or the "water of life", which is thought to refer to the fact the drink was once valued for its supposed medicinal qualities. In real terms whiskies are available in two styles – single malt and blended. Single malt is the premium whisky – referring to a whisky distilled at one site, only using malted barley. A blend refers to a whisky that is made from malted barley AND grain whisky. Grain whisky is a far cheaper and easier product to produce. Most blended whisky is created by mixing together a range of malts with the grain to create a whisky that will taste the same each and every time you drink it.
"Whisky" refers to the real stuff – Scotch – it's distilled and bottled in Scotland, and is a minimum of 40%ABV. "Whiskey" is the stuff made everywhere else – Japan, Canada, America, New Zealand (practically anywhere barley grows).
In Scotland there are five broad regions – Islay, the Islands, Campbeltown, the Lowlands, the Highlands, and Speyside. They each have differing styles, weight, and flavour.
Islay – An Island to the west of Scotland, it produces the peatiest (referring to the fuel used to spark the malting of the barley), saltiest, driest and strongest of Scotches. Ardbeg 10 is a benchmark Islay Scotch
Lowlands – Scotch made in the Southern part of Scotland is referred to as Lowland. It's generally light and heathery. A lot of Lowland whisky is used in blends. Glenkinchie 10 is a good example.
The Islands – This refers to any Whisky made off the coast of Scotland (excluding Islay). They're generally salty and smoky – and invoke images of rough weather and bonfires. There is a huge variation in Island whiskies as they could come from Arran (way down south) to the Orkney Isles (way up north). Try Highland Park or Talisker to experience the joy of Island whisky.
Speyside – The engine room of Scotch. This is where all the big names are, but is also where a lot of small guys make beautifully sherried whiskies. These are whiskies that will satisfy any lover of Scotch. GlenDronach 12 is the perfect example.
Campbeltown – Once this little town housed a heap of distilleries – now there are three/four – all pretty much owned by the same family. The whiskies produced here straddle the line between the other regions. Springbank is Speysideish with a foot in the Islands, Longrow is like a (lightly) peated Islay, and Hazelburn is Lowlandesque in style.
The Highlands – Pretty much anywhere on the mainland that doesn't fall in the other regions. There's a huge range of styles and flavours ranging from Old Pulteney in the North to Glen Goyne in the South.