Cargo

Cargo refers to any goods that are being transported across land, water, or air. While the term is often used broadly, there are specific ways to define its movement. In the field of economics, the term freight is used to describe goods moved for commercial gain at a specific freight rate. The concept of cargo also extends to the cold-chain. This includes perishable inventory that is always in transit toward an end-use. This transit can occur even while items are held in climate-controlled warehouses or cold storage.

Maritime shipping uses several distinct methods to move goods across the ocean. One method involves break bulk or general cargo. These are goods handled piecemeal rather than in large containers. They are often bundled in batches using cargo nets, slings, or crates. Workers may also stack them on pallets or skids. These items are typically lifted into a vessel's holds using cranes or derricks. If they are placed on the deck, stevedores must man-handle and stow them. To keep this cargo secure, workers use dunnage. Since the 1960s, the use of break bulk has declined as containers became more popular.

Another major maritime category is bulk cargo. These are commodities that are not placed in containers or on pallets. Bulk cargo is divided into two types: liquid and dry. Dry bulk examples include alumina, grain, gypsum, logs, and wood chips. Liquid bulk includes substances like oil and tallow. Some items, such as scrap metal, are also considered bulk. Unlike heavy-lift or project cargo, bulk items are not handled as individual pieces.

Air cargo provides a much faster way to move goods compared to other methods. Air freight specifically refers to goods carried in the cargo hold of a dedicated plane. Aircraft were first used to carry mail as cargo in 1911. Today, many aircraft are designed specifically for freight. The Boeing 747 is a common example. The An-124 was also purposely built to be easily converted into a cargo aircraft.

These large planes use standardized containers called unit load devices, or ULDs. ULDs are comparable to the ISO containers used on ships. They can be stowed in the lower decks or on the main deck of certain aircraft.

Land transportation relies heavily on both rail and road systems. Rail is used to transport massive amounts of water, cement, grain, steel, wood, and coal. Trains are efficient for long distances and direct routes. They are often more economical and energy-efficient than road transport when moving bulk loads. However, rail lacks flexibility and often requires transshipment costs. This happens when goods must be transferred between different modes of transport. Many governments encourage rail use because of its lower environmental impact.

Road transport is highly versatile and moves everything from letters to large containers. Companies like FedEx and Parcelforce use trucks of various sizes. Delivery trucks can range from small vans to massive semi-trucks. Freight on the road is often categorized by its size. Less-than-truckload, or LTL, represents the majority of business-to-business shipments. LTL shipments are often palletized and shrink-wrapped for mixed environments. In contrast, truckload, or TL, freight involves a single large shipment. In the United States, shipments larger than about 10,000 pounds are typically classified as TL. It is more economical for a large shipment to have exclusive use of a trailer.

Understanding the scale of these shipments helps explain global logistics. In the U.S., a fully loaded five-axle rig cannot exceed a specific weight set by the Federal Bridge Gross Weight Formula. Most long-haul equipment weighs about 80,000 pounds, leaving capacity for the freight. Shipments are also categorized by their service level. Express shipments are very small and often travel by air. Parcel shipments are larger boxes that typically move via road and rail. These categories help businesses manage how long an item stays in transit and how much it costs to move.