Sea containers are divided into two main groups: standard and non-ISO. Non-standard containers may resemble ISO containers in shape and size, but are not widely and consistently used due to lack of standardization.

Here, this article only considers containers according to ISO standards (ISO containers). According to ISO 6346 (1995), sea containers include 7 main types. The type of container is shown through the symbol on the container shell.

General purpose container.
Bulk cargo containers (Dry bulk containers / Bulk containers).
Specialized containers: transporting animals, cars...
(Named cargo containers: Livestock container, Automobile containers...).
Thermal container.
Open-top container.
Platform container (Platform container).
Tank containers (Tank containers).
 

1. General purpose container:

General merchandise containers are often used to transport dry goods, so they are also called dry containers (dry container, abbreviated as 20'DC or 40'DC). This type of container is most commonly used during sea loading.

2. Bulk containers:

A type of container that allows loading dry bulk goods (cement, grain, ore...) by pouring from the top down through the loading hatch (loading hatch), and unloading the goods at the bottom or side (discharge hatch). A normal bulk cargo container has an external appearance similar to a general merchandise container, except for the loading mouth and unloading door. The figure below shows a bulk container with the loading hatch (top) and unloading hatch (side) open.

3. Specialized containers (Named cargo containers):
A type specifically designed to carry a certain type of cargo such as cars, live animals, etc.

Car-carrying container: a structure consisting of a frame connected to the floor, without walls and a covered roof, specialized for carrying cars, and can be stacked inside 1 or 2 floors depending on the vehicle's height. (Currently, people still carry cars in grocery containers quite commonly).

– Solid containers: specifically designed for the material. The vertical wall or front wall has a small screen door for ventilation. The lower part of the vertical wall is arranged to escape the toilet.

4. Insulated containers (Thermal containers):

Designed to transport goods that require controlling the temperature inside the container at a certain level. Walls and roofs of this type are often covered with insulation. The T-shaped aluminum floor allows air to circulate along the floor and to empty spaces on the floor.

Insulated containers can often maintain hot or cold temperatures. Frequently encountered reefer containers (refer containers)

5. Open-top container:

Open-roof containers are designed to facilitate loading and unloading goods through the container roof. After packing, the roof will be covered with oilcloth. This type of container is used to transport machinery, equipment or wood with long trunks.

6. Platform container:

Designed with no walls, no roof but only a solid floor, specialized for heavy transportation such as machinery, equipment, iron and steel...

Flatbed containers have walls at both ends (front and back), this wall can be fixed, folded down, or removable.

7. Tank container:

A tank container basically consists of an ISO standard frame in which a tank is attached, used to transport liquid goods such as alcohol, chemicals, food, etc. Goods are poured in through the tank mouth (manhole) above the container roof, and are withdrawn. through the outlet valve by gravity or withdrawn through the tank mouth by a pump.

In fact, depending on the purpose of use, people also classify containers by size (20'; 40'...), by manufacturing material (aluminum, steel...).