Ale is a type of beer brewed using a warm fermentation method, resulting in a sweet, full-bodied and fruity taste. Historically, the term referred to a drink brewed without hops.

As with most beers, ale typically has a bittering agent to balance the malt and act as a preservative. Ale was originally bittered with gruit, a mixture of herbs or spices boiled in the wort before fermentation. Later, hops replaced gruit as the bittering agent.

Ale was an important source of nutrition in the medieval world. It was one of three main sources of grains in the diet at the start of the fourteenth century in England, along with pottage and breads.

Scholars believe grains accounted for around 80% of the calorie intake of agricultural workers and 75% for soldiers. Even nobles received around 65% of their calories from grains.

Small beer, also known as table beer or mild beer, which was highly nutritious, contained just enough alcohol to act as a preservative, and provided hydration without intoxicating effects. Small beer would have been consumed daily by almost everyone, including children, in the medieval world, with higher-alcohol ales served for recreational purposes. The lower cost for proprietors combined with the lower taxes levied on small beer inevitably led to the selling of some beer labeled "strong beer" that had actually been diluted with small beer.

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