Onion is a widely used vegetable in cooking, known for its distinct flavor and aroma. It belongs to the genus Allium and is closely related to garlic, shallots, and leeks. Onions come in various colors, including white, yellow, and red, and can be eaten raw or cooked in a multitude of dishes rich in vitamins, minerals, and antioxidants, onions offer several potential health benefits. They contain compounds like quercetin and sulfur compounds, which are believed to have anti-inflammatory and immune-boosting properties. Onions are also known for their prebiotic fiber content, which promotes a healthy gut microbiome and digestive system.