A lunch bag is a container used to carry food, typically for consumption during a meal or snack. It can be made from various materials such as paper, plastic, cloth, or metal and comes in different shapes and sizes depending on its intended use. Lunch bags are commonly used by people who bring their lunches to work, school, or other places where they may not have access to a kitchen or dining area. They can also be used for picnics, camping trips, or any outdoor activity where food needs to be transported and kept warm or cold depending on the contents.