Malt Whisky

What is malt whisky?

According to Wikipedia, malt whisky is simply whisky that's made from malted barley. Malt whisky from a single distillery is referred to as a single malt.

My understanding is that for a Scotch whisky to be considered as superior, it needs to be a single malt. Other than that, I'm not sure what the significance of the term 'malt whisky' actually is. But Wikipedia confirms that in Scotland, malt whisky must be aged for at least three years.

Are there any whiskies that don't need to be aged for three years? Or does whisky have to be made from malted barley?

In Ireland, all whiskeys must be aged for at least three years. In the USA the minimum age for malted whiskey is two years, and in other countries (e.g. Canada and Wales) the term "malt whisky" doesn't seem to be used.

England is often overlooked as a whisky-producing country, but after dying out in the late 19th century the English whisky industry has enjoyed a revival in the 21st. Malt whisky does seem to be a term that is used in respect of English whisky, but it's not clear to me whether there are laws relating to its use.

As stated above, the question appears to be correct: malt whisky does need to be aged for three years - in Scotland at least, and in Ireland as well.

Does the question refer specifically to Scotch malt whiskies? I'm not sure, but if it does then I think this should be made clear.