Beer is the world's oldest and most widely consumed alcoholic beverage and the third most popular drink overall after water and tea. It is produced by the brewing and fermentation of starches, mainly derived from cereals — the most common of which is malted barley, although wheat, corn, and rice are also widely used. Most beer is flavoured with hops, which add bitterness and act as a natural preservative, though other flavourings such as herbs or fruit may occasionally be included. Alcoholic beverages fermented from non-starch sources such as grape juice (wine) or honey (mead) are not classified as beer.

Some of mankind's earliest known writings refer to the production and distribution of beer: the Code of Hammurabi included laws regulating beer and beer parlours, and The Hymn to Ninkasi, a prayer to the Mesopotamian Goddess of Beer, served as both a prayer and as a method of remembering the recipe for beer in a culture with few literate people. Today, the brewing industry is a huge global business, consisting of several dominant multinational companies and many thousands of smaller producers ranging from brewpubs to regional breweries.

The basics of brewing beer are shared across national and cultural boundaries, and are commonly categorised into two main types — the globally popular pale lagers and the regionally distinct ales which are further categorised into other varieties such as pale ale, stout and brown ale. The strength of beer may range from less than 1% abv (alcohol by volume) to over 20% abv in rare cases, though is usually around 4% to 6% abv.

Beer forms part of the culture of various beer drinking nations, and has acquired various social traditions and associations, such as beer festivals and a rich pub culture involving activities such as pub crawling or pub games such as bar billiards.

History

main: History of beer

As almost any substance containing carbohydrates, mainly sugar or starch, can naturally undergo fermentation, it is likely that beer-like beverages were independently invented among various cultures throughout the world. The invention of bread and beer has been argued to be responsible for humanity's ability to develop technology and build civilization. The earliest known chemical evidence of beer dates to circa 3500–3100 BC from the site of Godin Tepe in the Zagros Mountains of western Iran.