Commercial breweries don't have to adhere to style guidelines and can call their beer whatever they think will get people drink it.
When I get home I can find an old post that gives some of the history of India Pale Ale, notice is not Indian. The first reference to what is now called IPA called it "Pale Ale as prepared for India."
Pale Ale itself started after they started using coke to malt grains, which prevented it from darkening too much. Before that all beer was at least amber because there were charred bits of grain that added color to the beer.
Anyway, fast forward, the East India Trading Company mostly brought good from India back to England. There was one particular brewery that make a pale ale that was more bitter than most others and was on the way for the ships leaving England and provided very favorable terms to ship captain's who were allowed to transport their own goods in their empty ships on thirty easy to India. So, this extra bitter pale ale became a popular choice. Turns out it also suited the tastes of British expats in the hot climate of India, and was one of the first beers served chilled.
Well one day a ship caring this beer crashed off the cost of England and was written off, which allowed local pubs to sell it. It was a hit.
Anyway, the biggest difference between IPA, English pale ale and American pale ale is the amount and variety of hops used.
English hops are earthy and floral, American hops are piney, curtsy and fruity. But it gets a little more complicated because typical English yeast strains produce esters that have a stone fruit quality.
American IPAs can be anything the Brewer wants to call an IPA, but do tend to be the most bitter and have the most focus on late addition hops which don't produce bitterness but do provide flavor and aroma that can be anything from pine to kiwi.
That's more than I like to type on my phone. I'm sure there are tons of autocorrect errors.
Thanks so much man, that is absolutely fascinating. If I don't like beer too bitter but are flavourful and lots of flagrant what are my choices? Sounds like either English/American would suit my taste best?
Also am I right in that malty beers are dark and hoppy beers are light?