Mayonnaise is a thick, creamy condiment commonly used in sandwiches, salads, and as a base for sauces and dips. It is typically made from a mixture of oil, egg yolks, vinegar or lemon juice, and seasonings such as salt, mustard, and sugar. The egg yolks act as an emulsifier, allowing the oil and vinegar/lemon juice to mix together smoothly. Mayonnaise is believed to have originated in Mahon, a city in Spain's Balearic Islands, during the 18th century. It was originally made with olive oil, but today it is most commonly made with vegetable oil. There are many variations of mayonnaise, including low-fat and vegan options.