One of the most underappreciated drivers of the modern global economy is the humble shipping container. Widely adopted internationally in the second half of the 20th century, intermodal containers largely supplanted break bulk cargo—the bags, barrels, pallets, and crates that must be individually loaded and unloaded onto ships, railcars, and trucks.

Intermodal containers are standardized in size and design, allowing them to be stacked onto large container ships, which can transport thousands of containers. In port, containers can be lifted onto railcars and flatbed trucks, enabling quick access to inland distribution centers and manufacturing facilities.

Containerization dramatically reduced costs all around. Fewer dockworkers were needed to load and unload vessels and larger ships were built thanks to stackable containers.