The concept of open systems, which became popular in the 1980s, is used to describe computer systems that can operate in harmony with different hardware and are built on open standards.

What is an Open System?

Any system can be described as open or closed. Closed systems are self-sufficient systems where nothing can enter or exit. Open systems, on the other hand, are interactive systems that engage with their external environment. Open and closed systems, part of systems theory, are encountered in various fields like physics, biology, chemistry, computer science, and economics.

In information technology, open systems appear as open-source software and open standards. Today, open systems, where different hardware and software work together, have become commonplace. However, in the past, especially in the 1980s when each manufacturer provided their own hardware and software together, the concept of open systems was quite remarkable.

To better understand open systems, let's continue with an example: Nowadays, PCs are created by assembling hardware developed by different manufacturers according to certain standards. This situation leads to PCs being classified as open systems. PCs are open to external intervention, allowing changes to be made to the system with different hardware if desired.

From a software perspective, the ability for everyone to view the source code of software means that software is considered open-source software. Open systems do not always have to use open-source software. Continuing with the PC example, the Windows operating system, which has closed-source code, can be used in open systems.

Open Source Software

Open-source software has surpassed the concept of open systems today. As the interoperability of computer systems' hardware has become standard, open-source has become even more significant on the software side.

Open-source software, or software with open-source code, is software whose source code is shared openly for everyone to access. These software programs allow for modifications and redistribution under certain licensing rules. One of the most well-known open-source software examples is Linux-based operating systems. The open-source culture is increasingly being adopted.

Open Standards

The foundation of open systems is open standards. Standards that are available for use by everyone are called open standards. Thanks to open standards, mobile phones can operate the same way worldwide today. Photos taken with any camera can be viewed on different computers or devices.

Many technologies developed in the field of information technology are standardized and made available to everyone. This allows for the development of devices produced by different manufacturers but working in harmony with each other. Standards are mostly determined by non-profit organizations. The World Wide Web Consortium (W3C) and the Internet Engineering Task Force (IETF) are examples of such organizations working on the standardization of internet technologies.