Some of the most common types of containers:

20ft General Purpose Container
Inside Dimensions 5,9 x 2,352 x 2,395 m
Useable volume 32,2 m³
Tare (tons) 2,350
Max Payload (tons) 28,130

Entirely enclosed, used to load most types of goods.
20ft open top container
Inside Dimensions 5,895 x 2,35 x 2,340 m
Useable volume 32,5 m³
Tare (tons) 2,450
Max Payload (tons) 30,050
With flexible and movable or removable top, used to load most types of goods and heavy or oversized goods.
With collapsible sides to be folded, stackable, used to load oversized goods.
40ft Flat Rack
Inside Dimensions 11,652 x 2,347 x 2,245 m
Tare (tons) 5,9
Max Payload (tons) 49,1
20ft open side container
Inside Dimensions 5,898 x 2,267 x 2,299 m
Useable volume 31,30 m³
Tare (tons) 3,180
Max Payload (tons) 20,820
Side opening to ease the loading and unloading, used to load most types of goods.

Other types of containers

Double door/tunnel
With doors on both ends, used to ease the loading and unloading of goods that need wider space.