Systems are sets of entities, physical or abstract, comprising a whole where each component interacts with or is related to at least one other component and they all serve a common objective. The scientific research field which is engaged in the interdisciplinary study of universal system-based properties of the world is general system theory, systems science and recently systemics. This field investigates the abstract properties of matter and mind, and their organization, searching for concepts and principles which are independent of the specific domain, substance, and type of system, and of the spatial and/or temporal scales of its existence.
Systems science can be viewed as ... "a metalanguage of concepts and models for interdisciplinary use, still now evolving and far from being stabilized. This is the result of a slow process of accretion through inclusion and interconnection of many notions, which came and are still coming from very different disciplines. The process started more than a century ago, but has gathered momentum since 1948 through the pioneering work of Norbert Wiener, John von Neumann, Ludwig von Bertalanffy, Heinz von Foerster and W. Ross Ashby, among many others" (Charles François, 1999).
Joseph Francis Shea (September 5, 1926–February 14, 1999) was an aerospace engineer and NASA manager. As head of the Apollo Spacecraft Program Office, Shea played a key role in shaping the course of the Apollo program, helping to lead NASA to the decision in favor of lunar orbit rendezvous and supporting "all up" testing of the Saturn V rocket.
Shea's speciality was systems engineering: a new type of engineering in the 1950s that focused on the management and integration of large-scale projects, turning the work of engineers and contractors into one functioning whole. He played a significant role in the Titan I project; as George Mueller writes, "he contributed a considerable amount of engineering innovation and project management skill and was directly responsible for the successful development of this pioneering guidance system...."