India Pale Ale is a type of beer, like a Stout or Pilsner. India Pale Ales are commonly referred to as IPAs and are part of the Pale Ale category of beers; the term Pale Ale derives from the type of pale malt the ale is brewed from.
India Pale Ales date back to the 1800's when large shipments of beer were being transported from England to India. One specific brewery added higher amounts of hops and alcohol to the beers being shipped to India, to keep the brews from going skunky.
This extra love, in the form of more hops and alcohol, given to the beer headed to India was a hit. More people and breweries caught on and this type of beer became more and more popular at home, in England, and abroad.