(1) What is a system?

•  A system can be defined as a set of detailed methods, procedures and routines created to carry out specific activity or to perform a duty or to solve a problem.
•   All systems generally have:

a.  inputs, outputs and feedback procedures,

b.  consistent steady state inspite of changing external environment,

c.   boundaries as defined by system observer.

• Within a larger system, there may be few sub-systems.
•  Functioning of system is impacted when an element is modified significantly or removed.