open system

A system that allows third parties to make products that plug into or interoperate with it. For example, 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.

For years, the term "open systems" (plural) referred to the Unix world because Unix runs in more types of computer hardware than any other operating system. Contrast with closed system.

Open Systems Vs. Open Source
Open systems refers to open platforms, whereas open source refers to the software's source code and rights regarding its redistribution. Open systems may employ open source software or proprietary software. See open source.

Open Systems Vs. Open Standards
Open systems may or may not employ open standards, the PC being the prime example. However, open standards imply open systems, and the two terms are often used synonymously. See open standards.