Open and Closed System

OPEN SYSTEM: A system that allows third parties to make products that plug into or interoperate with it. For years, the term "open systems" (plural) referred to the Unix world because Unix ran in more types of computer hardware than any other operating system OR
Open systems are computer systems that provide some combination of interoperability, portability, and open software standards. It can also mean specific installations that are configured to allow unrestricted access by people and/or other computers.

EXAMPLES:
The PC is an open system. Although the fundamental standards are controlled by Microsoft, Intel and AMD, thousands of hardware devices and software applications are created and sold by other vendors for the PC. Mechanical engineering texts on thermodynamics are more concerned with extraction of work from engines and turbines and therefore emphasize open systems.

CLOSED SYSTEM: A system in which the specifications are kept secret to prevent interference from third parties. It inhibits third-party software from being installed; it keeps third-party hardware from interoperating with it, and it prevents third-party enhancements from improving the product.
EXAMPLES:
Calorimetry experiments often use a closed system, especially bomb calorimeters. Most experiments in chemistry are conducted as closed systems.

DIFFERENTIATION BETWEEN OPEN AND CLOSED SYSTEM
OPEN SYSTEM:
A system that receives inputs of energy and matter and then outputs materials into surrounding environments is termed: Open System
For example the systems in human body
CLOSED SYSTEM:
A system that is shut off from the surrounding environment and is self-contained is termed: Closed System.
For example the earth