How to move goods by sea

Many different types of ship are used to transport goods around the world. The differences between them reflect the varied needs of international traders. In particular, different types of ship are used to carry different types of cargo, or to carry cargo in varied ways.

The different types of ship are summarised below:

• Container ships (or 'box ships') carry their cargo packed into standard 20' or 40' containers that are stacked both on and below deck. Smaller 'feeder' ships carry containers on coastal and inland waters.
• Roll-on/roll-off (ro-ro) vessels carry both road haulage and passenger vehicles. For more information about road haulage, see how to move goods by road.
• General cargo ships carry loose-packaged cargo of all types.
• Bulk carriers carry unpackaged goods - usually large volumes of single-commodity goods such as grain, coal, fertilisers and ore.
• Tankers carry liquids (such as oil and gas) in bulk.

Merchant ships primarily do business in two different ways:

• Liner vessels operate on fixed routes, to fixed schedules and usually with a standard tariff. Liner trades are dominated by container ships, roll-on/roll-off carriers and general cargo ships.
• Charter ('tramp') vessels operate entirely according to the demands of the person chartering them. Their ports of loading and discharge are set by the charter, as is their cost, which depends on immediate supply and demand conditions. Most tankers and bulk carriers operate in the charter markets.