Open System

An open system may refer to:Open system (computing), one of a class of computers that provides some combination of interoperability, portability and open software standards, particularly Unix and Unix-like systemsOpen system (computer science), in the computer sciences a collection of interacting software, hardware, and human components with well-defined, publicly available interfaces maintained by a consensus processOpen system (management science), in management science a system that is capable of self-maintenance on the basis of throughput of resources from the environmentOpen system (systems theory), a system where matter or energy can flow into and/or out of the system, in contrast to a closed system, where energy can enter or leave but matter may notOpen System (music) - collaborative project of Indidginus & Matt Hillier.
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Open systems are computer systems that provide some combination of interoperability, portability, and open software standards. (It can also mean systems configured to allow unrestricted access by people and/or other computers; this article only discusses the first meaning.)The term originated in the late 1970s and early 1980s, mainly to describe systems based on Unix, especially in contrast to the more entrenched mainframes and minicomputers in use at that time. Unlike older legacy systems, the newer generation of Unix systems featured standardized programming interfaces and peripheral interconnects; third party development of hardware and software was encouraged, a significant departure from the norm of the time, which saw companies such as Amdahl and Hitachi going to court for the right to sell systems and peripherals that were compatible with IBM's mainframes.
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open systems, computer system which operates under agreed standards and enables it to work with all types of hardware and software

A system with characteristics that comply with specified, publicly maintained, readily available standards and that therefore can be connected to other systems that comply with these same standards.

any system or enterprise (nation or business firm) that is affected by external forces.