Is whisky distilled from beer?

If you're talking about Scotch whisky, the answer is yes! And it's known as "distiller's beer", made from just barley, yeast, and water.

Some more info here: http://www.maltmadness.com/malt-whisky/beginners-guide-04-distilling.html

One big difference is that distilled spirits are fermented at relatively high temperatures (70s-80s) to speed up the yeast and produce as much alcohol as possible. This also results in undesirable components like higher-order alcohols and methanol which are later removed in the "heads" and "tails" of distillation.

This is why homemade "bathtub gin"-style liquor during prohibition could be dangerous, because the people making it often skipped this step.

Whiskey is typically made primarily from corn (fermented in the same way as beer) and then distilled. The trick is, after distillation it has to be aged in wood barrels for a couple years, which is what gives it the flavor and color.

Technically you can distill beer. If you do it a couple times you'll basically end up with the same spirit, which can then be aged in a barrel the same way, but corn is much easier, cheaper and traditionally the main ingredient.