Operating Systems

An Operating System or OS is a software program that enables the computer hardware to communicate and operate with the computer software. Without a computer Operating System a computer would be useless.

Microsoft Windows Operating Systems
Microsoft Windows is a range of closed-source operating environments for personal computers. The range was first introduced by Microsoft in 1985 and eventually came to dominate the world personal computer market. All recent versions of Windows are fully-fledged operating systems.

Linux Operating Systems
Linux (pronounced Lih'Nuks) is a computer operating system. It is probably the best known example of free software and of open-source development. "Linux" strictly refers to the Linux kernel, but the name is often used to describe the entire Unix-like operating system formed by combining the Linux kernel with the GNU libraries and tools. Linux supports a vast range of computer hardware and has been deployed in applications ranging from personal computers to supercomputers and embedded systems such as mobile phones and the TiVo PVR.

Unix Operating Systems
The UNIX operating system was developed at AT&T. Because it was essentially free in early editions, easily obtainable, and easily modified, it achieved wide acceptance. Later it was the choice starting point for developing operating systems for evolving minicomputers. Due to its earlier widespread use it exemplified the idea of a operating system that was conceptually the same across various hardware platforms. It still was owned by AT&T and that limited its use to groups or corporations who could afford to license it.

IBM OS/2 Warp
IBM and Microsoft announced they were working together on future PC operating systems.
Microsoft wanted to use Windows, while Big Blue pushed its own code. The issue was still unresolved when the two companies announced OS/2, Version 1.0 in April 1987. OS/2 was originally writen for the 286. The 286 had introduced what Intel called "protected" memory and the ability to write programs beyond the 640K barrier, but it did so in a way that sometimes made it incompatible with existing 8088/8086 based software.

Mac OS
Mac OS is Apple Computer's operating system for Apple Macintosh computers. Mac OS was the first commercially successful operating system which used a graphical user interface - although early versions did not use that, or any, name.

MS-DOS
On August 12, 1981, IBM introduced its new revolution in a box, the "Personal Computer" complete with a brand new operating system from Microsoft and a 16-bit computer operating system called MS-DOS 1.0.