WBS stands for work breakdown structure. Wikipedia defines it as: „A hierarchical and incremental decomposition of the project into phases, deliverables and work packages. It is a tree structure, which shows a subdivision of effort required to achieve an objective; for example a program, project, and contract.
In a project, the WBS is developed by starting with the end objective and successively subdividing it into manageable components in terms of size, duration, and responsibility (e.g., systems, subsystems, components, tasks, subtasks, and work packages) which include all steps necessary to achieve the objective.“
Wikipedia goes on to claim that WBS was developed by the United States Department of Defense and was introduced by the U.S. Navy in 1957 to support the development of the Polaris missile program.
Breaking down complexity into its component parts in order to focus on what is truly critical is hardly a development of any human organization of the 20th Century. Surely it is has been fundamental to human thinking for quite some time.