Ports are coastal points where ships can dock at natural or artificial harbors to load and unload passengers, crew, and cargo. Artificial harbors, typically built specifically for use as ports, are made through dredging or the construction of sea walls, jetties, or breakwaters. The ports of Houston, Texas, and Long Beach, California, are especially large American artificial harbors (Houston is the country's busiest port for foreign tonnage). Certain ports are deepwater ports, enough so to accommodate fully laden Panamax ships—the largest size of ship that can pass through the Panama Canal.

A port of call is a port used as an intermediate stop for a cargo ship, such as for refueling or unloading part of the cargo. For cruise ships, a port of call is the ...