The operating system provides several essential functions, including: 1. managing the hardware resources of the computer; 2. providing the user-interface components; 3. providing a platform for software developers to write applications.
All computing devices run an operating system. For personal computers, the most popular operating systems are Microsoft’s Windows, Apple’s OS X, and different versions of Linux. Smartphones and tablets run operating systems as well, such as Apple’s iOS, Google’s Android, Microsoft’s Windows Mobile, and Blackberry.
Early personal-computer operating systems were simple by today’s standards; they did not provide multitasking and required the user to type commands to initiate an action. The amount of memory that early operating systems could handle was limited as well, making large programs impractical to run. The most popular of the early operating systems was IBM’s Disk Operating System, or DOS, which was actually developed for them by Microsoft.