Shipping containers are standard dimensions waterproof cargo containers used for transport, especially maritime, although there are also trailers for trucks adapted to transport these containers. The square prism shape that the containers have makes them perfect for transport, they can be arranged and stacked maximazing the available space, and also can be easily stacked up to 7 stories, as high as you can see in the photo above . Normally enterprises tend to collect them on the outside without fear that their cargo can be affected by the weather conditions, because they are 100 % waterproof , it also makes them ideal for using them as dwellings.
Containers can be used to carry whatever cargo that can fit into their dimensions, these dimensions are standardized according to international ISO standards and they are basically:
The total width is always 8 ft ( 2.44 m)
Its length is usually between 20 and 40 feet , they can also be smaller and larger but their use is not very common in the house construction.
There are also 3 different heights, the most recommended for use as homes are the highest , the 9,5 ft (2,896m), although these are usually the most expensive because they are not so easily to find.
Generally the shipping containers are made from steel, but they can also be made of other materials such as aluminum, plywood , etc . Shipping containers also feature a twist-lock fittings, used for attach them to boats and trailer trucks .
For more information please take a look at the Wikipedia page: