A operating system (OS) is software that manages the hardware or the computer. It also provides common services for the operating system. The operating also manages the memory of the computer. A operating system would usually have a kernel that talks directly to the hardware
Types of operating systems
Single tasking and multi tasking system
A single tasking system can only run one program at one time while a multi tasking operating system allows more than one program to run. This can be done using time sharing where the CPU time is shared across the processors.
Single-user and multi-user
Single user operating system have no ways to differentiate between users but may allow you to multitask. A multi-user operating system allows you to have several users to control a OS and a admin can manage the permissions.
Real-time
A real time operating system is a system that needs to be able to process data in real time. This can be used if a system is reliant on data that has to be processed quickly.
Embedded operating system
A embedded operating system runs on a small computer that is specialised for a small machine or component. These operating systems have limited functions and are programmed onto the ROM of the system.
Examples
Kernel
Main wiki page: Operating system kernel 400 A operating system kernel talks to the hardware and applications. It has complete control of the CPU, RAM, input devices and output devices