Operating Systems

Introduction

Operating Systems are essential parts of a computer system. They form a way for a connection to be made between software and hardware and provide several services such as memory management and other helpful facilities in order for applications to function properly and take advantage of the hardware offered.

Background

While Operating Systems were developed before the time period this website covers, it is important to have some background to understand why they were developed in the first place. The first computers had no Operating Systems - they were controlled manually using plug boards. This is rather inconvenient and thus started a market for Operating Systems, a way to assist the user operating the machine with tasks involving, for example, input and output.

History

Operating Systems in the 1960s started to take advantage of all of the computer’s resources and run several jobs at the same time. This allowed for the concept of multiprogramming to be implemented. This is similar to the idea of multitasking where multiple programs are running simultaneously.

Another technique implemented around this time was spooling². This involves data for a slow-running device being placed into storage and when the device is ready, it can retrieve it and work on it. This stops the bottleneck where the computer would wait for the device to be ready before continuing operations, since the data to be worked on is saved elsewhere and ready for reading by the device when it can work on the data.

With the evolution of microprocessor technology came more power to desktop computers, giving them as much power as was available on mainframe computers in the 1970s. With this expansion came the 2 main base Operating Systems of this period - MS-DOS, created by Microsoft for Intel processors, and UNIX which was dominant on the Motorola 6899 family.