Functions and Evolution of an Operating System

Operating systems have evolved from slow and expensive systems to present-day technology where computing power has reached exponential speeds and relatively inexpensive costs. In the beginning, computers were manually loaded with program code to control computer functions and process code related to business logic.
An operating system has three main functions: (1) manage the computer's resources, such as the central processing unit, memory, disk drives, and printers, (2) establish a user interface, and (3) execute and provide services for applications software.