Sandwiches are a popular type of lunch food, taken to work, school, or picnics to be eaten as part of a packed lunch. The bread may be plain or be coated with condiments, such as mayonnaise or mustard, to enhance its flavour and texture. As well as being homemade, sandwiches are also widely sold in various retail outlets and can be served hot or cold. There are both savoury sandwiches, such as deli meat sandwiches, and sweet sandwiches, such as a peanut butter and jelly sandwich.