This article is from the rec.food.drink.beer FAQ, by John Lock with numerous contributions by others.
Beer is an alcoholic beverage made from malted grains, hops, yeast,
and water. The grain is usually barley or wheat, but sometimes corn
and rice are used as well. Fruit, herbs, and spices may also be used
for special styles. In the distant past, the terms "beer" and "ale"
meant different things. "Ale" was originally made without using hops,
while "beer" did use hops. Since virtually all commercial products
now use hops, the term "beer" now encompasses two broad categories:
ales and lagers.
 
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