Systems are usually defined either in the context of thermodynamics or cybernetics. However, a more general system theory is being developed that includes categorical dynamics, quantum computers, fuzzy systems and economical or social systems.
- An information system is usually a database.
- A computer system is just a programmed automaton
- A philosophical system is a general framework for philosophical discussion, such as ontological, epistemological, metaphysical, etc.
- An economic system is usually defined by a corresponding ideology and is in theory controlled by different types of societies, such as : medieval, primitive, utopian, modern, and so on.
- A quantum system is non-deterministic, whereas a classical system is deterministic--with a strict causality
- A dynamic system is usually represented by a 'system' of differential equations (ODE's) that admit integrable solutions
- A chaotic system is neither quantum nor classical, although like the classical system it is still deterministic
- An anticipatory system is characteristic of organisms and also of some societies
- A complex system--unlike a simple one-- cannot either be decomposed into its components without ceasing to function or cannot be completely simulated by computer models.
An interesting exception is the Environment as it has no strict boundaries, only a horizon, and therefore it cannot be represented as a system.
The term system may be used in many other contexts, e.g. Solar System and System of Government.