A Brief History of Operating Systems

• Operating Systems (OS) are the layer of software that sits between hardware and higher level pieces of function like applications and middleware. They help applications and middleware make use of the underlying hardware by doing things like managing memory, providing device driver support for hardware components and file systems to store and organize information on disk.

• While not technically part of the operating system layer, many modern operating systems are package some higher level function such as shells (also known as graphical user interfaces (GUI)), storage compression, firewalls, internet access, and even web browsers. This paper is a brief overview of the key operating systems in the market, their ancestry, their design points and their differentiating features.

• These were the first operating systems and this still describes the basic function of an OS. Operating systems evolved and it became common to bundle generally used utilities and applications with the base OS function.