The short answer
IPA stands for India Pale Ale. Today, very different beers go by that name — from clear and distinctly bitter to hazy and strongly fruity. The description on the label tells you more than the three letters do.
What West Coast, New England and Double mean
West Coast IPA is usually clear and distinctly bitter. New England IPA is often hazy and tastes juicy and fruity. Double IPA means: stronger and more intense. Session IPA means: lower alcohol. The exact amount is on the label.
The name is misleading. The story of heavily hopped beer for the sea voyage to India is well known, but only partly documented. It doesn't help when shopping: what's called IPA today has little to do with the original — and sometimes even less to do with each other.
A fruity aroma doesn't mean fruit was added
Hops naturally smell fruity on their own. Whether fruit was actually added is stated in the ingredients list. So a beer that smells like mango isn't necessarily a mango drink.
If you want to get to know IPAs, pick two deliberately different ones. Judge the aroma and bitterness separately. That way you'll quickly notice which direction suits you.
Freshness matters more with IPA than with any other beer. The hop aromas break down within a few months. A six-month-old IPA tastes like what's left over: bitterness without aroma. Look on the can for the packaging date, not just the best-before date.
