Break-bulk Vessel
Break bulk cargo or general cargo is a term that covers a great variety of goods that must be loaded individually, and not in inter-modal containers nor in bulk as with oil or grain. Ships that carry this sort of cargo are often called general cargo ships.
RORO Vessel
RORO vessels have built-in ramps that allow the cargo to be efficiently rolled on and off the vessel when in port. While smaller ferries that operate across rivers and other short distances often have built-in ramps, the term RORO is generally reserved for larger oceangoing vessels. The ramps and doors may be stern-only, or bow and stern for quick loading.
Tug & Barge
Tugs move vessels that either should not move themselves, such as ships in a crowded harbor or a narrow canal, or those that cannot move by themselves, such as barges, disabled ships, log rafts, or oil platforms. A barge is a flat-bottomed boat, built mainly for river and canal transport of heavy goods. Some barges are not self-propelled and need to be towed or pushed by Tugs.