The main ingredient in a meringue is egg whites. When whipped, egg whites can incorporate air, helping them to achieve a light, airy texture. This process also requires the addition of sugar, which stabilizes the foam and gives meringue its characteristic sweetness. Meringue can be made into different styles, such as French, Swiss, or Italian, depending on the method of preparation. It is a versatile component in desserts, used to create toppings for pies, form delicate cookies, or even as a base for more complex confections, showcasing its culinary flexibility.