Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes.
The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients.
Grape wine is produced by fermenting crushed grapes using various types of yeast.
Yeast consumes the sugars in the grapes and converts them into alcohol. Different varieties of grapes and strains of yeasts produce different types of wine.