A bulk carrier, bulk freighter, or bulker is a merchant ship specially designed to transport unpackaged bulk cargo, such as grains, coal, ore, and cement in its cargo holds. Since the first specialized bulk carrier was built in 1852, economic forces have fuelled the development of these ships, causing them to grow in size and sophistication. Today's bulkers are specially designed to maximize capacity, safety, efficiency, and durability.
A Tanker (or tank ship or tankship) is a merchant vessel designed to transport liquids or gases in bulk. Major types of tankship include the oil tanker, the chemical tanker, and gas carrier. In the United States Navy and Military Sealift Command, any type of tanker used to refuel other ships is called an oiler.
These are cargo vessels that regularly transport goods, supplies or equipment in support of exploration or production of offshore mineral or energy resources. Offshore supply vessels are typically operated by shipowners: either companies set up specifically to own and operate such vessels or companies combine with other vessel operations like salvage, shipping, etc.