In 1830s, railroads began transfering and transporting containers that would be loaded on trucks and ships, but it was small compared to today's steel containers. Circa 1840s, iron boxes and heavy wooden boxes were introduced, and around the early 1900s saw the usage of closed container boxes made especially to move or transport things between the road and the railroad.

In the 20th century, the United Kingdom began to use similar containers and in the 1920s, the Railway Clearing House (RCH) standardised the RCH Container (five or ten foot long, wooden, non-stackable)

The United States Army began using specialized containers to speed up the loading and unloading of transport ships just toward the end of WW2. The army used the term "transporters" to identify the containers, for shipping household goods of officers in the field. During the Korean War the transporter was evaluated for handling sensitive military equipment, and proving effective, was approved for broader use. Theft of material and damage to wooden crates, in addition to handling time, by stevedores at the Port of Pusan, proved to the army that steel containers were needed. In 1952 the army began using the term CONEX, short for "Container Express". After the U.S. Department of Defense standardized an 8'x8' cross section container in multiples of 10' lengths for military use it was rapidly adopted for shipping purposes.

These standards were adopted in the United Kingdom for containers and rapidly displaced the older wooden containers in the 1950s.
What Are They and For What

Types

There are several types of containers for different purposes and needs:
General purpose containers for cartons, cases, sacks, high or half height
High cube palletwide containers for europallet compatibility
Temperature controlled from 25'C to +25'C reefer
Open top bulktainers for bulk minerals, heavy machinery
Open side for loading oversize pallet
Flushfolding flat-rack containers for heavy and bulky semi-finished goods, out of gauge cargo
Platform or bolster for barrels and drums, crates, cable drums, out of gauge cargo, machinery, and processed timber
Ventilated containers for organic products requiring ventilation
Tank containers for bulk liquids and dangerous goods
Rolling floor for difficult to handle cargo
Gas bottle
Generator
Collapsible ISO
Swapbody

Other uses for Containers

There are variety of uses for steel containers todate. Some of the companies are using them to build houses, as a cabin, or even a workshop. It can also be used as storage area for industries, constructions and lots more.

Nowadays, we can see that they are being used to store computer data centres, and Sun Microsystems was the first to do this.