A container is a standardized, reusable, and stackable cargo unit designed for the efficient transport and storage of goods in the supply chain. Containers are typically made of steel or aluminum and come in various sizes, such as 20 feet or 40 feet in length. They provide a secure and protected environment for the goods during transportation, reducing the risk of damage and facilitating the smooth handling and transfer of cargo between different modes of transportation, such as ships, trains, and trucks.