Over 90% of world trade travels by sea. The international merchant fleet employs some 1,250,000 seafarers at sea. A further 250,000 are estimated to be on shore, in training, on leave or looking for work. It is believed that more than 60% of seafarers come from a Catholic Christian background.
| Region of origin | Percentage of total |
| Philippines | 20 |
| Other Far East countries | 20 |
| Eastern Europe | 28 |
| OECD | 13 |
| South Asia & Middle East | 11 |
| Latin America & Africa | 8 |
Chart to show origins of seafarers in the merchant fleet
source: Lane A D, Obando-Rojas B, Wu B, Tasiran A (2002) Crewing the International Merchant Fleet, Lloyd's Register - Fairplay Ltd.
Despite developments in road and air transport, it is still easier to transport heavy or large cargoes by coastal or long distance ships. Demand for cargo ships is increasing with the expansion of world trade. Minerals such as coal, iron, bauxite, copper and chrome are loaded into ships by conveyor belts. Dry cargoes such as cereals, sugar, fertilisers, and fodder for livestock are stored silos in ports before being transferred to the holds of ships. Perishable foodstuffs are carried in refrigerated ships.
Container ships carry their cargoes in metal boxes, 20 – 40 foot in length. These boxes can be loaded and unloaded very rapidly by portside cranes. Container ships can be in and out of port in a matter for hours. This is highly advantageous for shipping companies anxious to minimise what they pay in port dues. For the hardworking seafarer it means even less possibility of spending time ashore. This type of shipping has grown steadily in the last 30 years.
Oil tankers may carry hundreds of tons of crude oil. Pipelines carry oil to coastal terminals where it is loaded into the tankers and transported to depots or refineries in consumer countries. Other fuels such as petroleum and gas are carried in specilised tankers. Security is paramount as such ships have the potential to be floating bombs.
click here to read about life onboard a tanker carrying liquid petroleum gas
Voyagers on the sea in ships,
plying their trade on the great ocean,
have seen the works of Yahweh,
his wonders in the deep...

A container ship