Onion is a bulbous vegetable with layers of papery skin and a strong aroma. It comes in various colors, including white, yellow, and red, and has a sharp, spicy flavor when raw. Onions are commonly used in cooking to add flavor and depth to dishes. They can be chopped, sliced, or minced and used in soups, stews, stir-fries, sauces, and salads. Onions can also be caramelized or sautéed to bring out their natural sweetness. They are rich in vitamins and minerals, particularly vitamin C and potassium, and contain antioxidants that may offer health benefits.