A specific parameter characterizing System behaviour (it's structure and interrelation or interaction of System components) during the evolution or in response to external influence.
The System property may be Constant (taking one value only) or Variable (which may take different values over time or in response to external influence ).
The System property may be static (always stays constant over time) or dynamic.
A System property not is not necessarily is a property of each System component and may characterize a System as a whole.
For example, a massive matter consist of atoms which are component so fa system while temperature characterising the system as a whole entity and not the property of each atom.
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