The development of shipping containers reached a turning point in the late 1970s when standardization began to take place. Prior to this time numerous designs and sizes of containers were seen throughout the world. The true intermodal era began in the 1980s with the expanding world economy, Panama Canal ship size restrictions, intermodal railway car (wagon) designs and the setting of ISO standards for international shipping containers.
Steel became the norm and the standard-height (8ft 6in) 20-foot containers eventually became standard worldwide.
In addition to ISO size standardization, assembly-line manufacturing standardization brought the steel container from various aluminum and steel designs to a more similar design. In the late 1970s squared corrugations with double logo panels were the common new-builds.
