India Pale Ale (IPA, also known as Strong Pale ale and Imperial Pale ale), is a distinct style of beer and is characterized as a sparkling pale ale with a high level of alcohol (5.5% to 6.3% by volume) and hops, thus having an increased bitterness (typically 35-48 on the IBU scale). The creation of India Pale Ale (IPA) during the 1790s was the result of tremendous efforts by British brewers to overcome a difficult problem: during the 1700s beer did not keep well on long ocean voyages, especially into hot climates. These hot environments resulted in the arrival of flat, sour beer.