Apple cider vinegar is made from fermented apple juice. To make it, apples are crushed and mixed with yeast and bacteria. The mixture is then allowed to ferment for several weeks. During this time, the sugars in the apples are converted into alcohol. The alcohol is then converted into acetic acid, which gives apple cider vinegar its sour taste. Finally, the vinegar is filtered and bottled. While most commercial vinegars are made using artificial methods, apple cider vinegar can also be made naturally at home.