Originally released in 1997, Uniclass allowed project information to be structured to a recognised standard.
Early versions were criticised for not being unified, for inconsistencies between the labelling and depth of tables, for poor integration of civil engineering and building works, and for being an essentially paper-based system.
The suite of tables[3] are broadly hierarchical, and allow information about a project to be defined from the broadest view of it to the most detailed.
By selecting pairs of numbers, up to 99 items can be included in each group of codes, allowing plenty of scope for inclusion.
For example, Systems are arranged in groups with subgroups which are sub divided, which leads to the final object code.