Onion (Allium cepa) is a widely cultivated vegetable known for its pungent flavor and numerous health benefits. It is a member of the Amaryllidaceae family and is grown in various climates across the world. Onions are rich in vitamins, minerals, and antioxidants, particularly vitamin C, vitamin B6, and quercetin, which contribute to immune support and overall health. They are used extensively in culinary dishes, adding flavor to soups, curries, salads, and sauces. Onions come in different varieties, including red, white, and yellow, each with distinct taste and culinary uses. The crop grows well in well-drained soil and requires moderate water and sunlight. Major onion-producing countries include China, India, the United States, and Egypt. Beyond cooking, onions have medicinal properties, such as anti-inflammatory and antibacterial effects, making them a valuable ingredient in both food and natural remedies.