From Wikipedia:
A system (from Latin systēma, in turn from Greek σύστημα systēma, “whole compounded of several parts or members, system”, literary “composition”[1]) is a set of interacting or interdependent components forming an integrated whole.
A system is a set of elements (often called ‘components’ instead) and relationships which are different from relationships of the set or its elements to other elements or sets.
Fields that study the general properties of systems include systems theory, cybernetics, dynamical systems, thermodynamics and complex systems. They investigate the abstract properties of systems’ matter and organization, looking for concepts and principles that are independent of domain, substance, type, or temporal scale.
Most systems share common characteristics, including:
Systems have structure, defined by components/elements and their composition;
Systems have behavior, which involves inputs, processing and outputs of material, energy, information, or data;
Systems have interconnectivity: the various parts of a system have functional as well as structural relationships to each other.
Systems may have some functions or groups of functions
The term system may also refer to a set of rules that governs structure and/or behavior.
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