Main Port: A main port is a port with big capacity of cargo handling, acting as a hub or a gateway for goods transportation in its area. In most case, main ports are included on liner's freight tariffs and have regular container liners(mother vessels) to berth at.
Feeder Port: Feeder Ports are ports for feeder vessels to collect shipping containers from and transport to central container terminals or transshipment hubs (main ports), where containers are loaded to mother vessels for further transport.
Dry Port: A dry port is an inland intermodal terminal directly connected by road or rail to a seaport, operating as a centre for the transshipment of sea cargo to inland destinations.
City Port: The category “City Port” here means a city with one or more container ports included. When a city is used to represent all its ports, we will just call it “Port of *****”(like “Port of Shenzhen”).