A water-in-oil emulsion is a mixture where tiny droplets of water are dispersed in a continuous layer of oil. This type of emulsion is commonly found in products like butter and certain cosmetics. The water droplets are stabilized by emulsifiers, which help prevent them from coalescing and separating from the oil. In a water-in-oil emulsion, the oil phase is the dominant component, making it thicker and creamier than other emulsions, such as oil-in-water emulsions. These emulsions are often used in food, pharmaceuticals, and personal care products due to their unique texture and ability to encapsulate flavors or active ingredients.