A collection of software that manages computer hardware resources and provides common services for application software. Designed to support a computer’s basic functions. Often provides a graphical user interface for the user to interact with the OS.
Kinds of OSs
Type of OS
Often comes as two kinds of operating systems:
- desktop operating systems — installed on personal computers meant to be used by one person at a time; and
- the Windows and macOS families of operating systems are examples of desktop OSs
- server operating systems — installed on more powerful computers (servers) connected to a network and sets out rules enabling multiple users to access information.
- the Windows Server family of operating systems are examples of server OSs
Open-source and closed-source OSs
Operating systems may also vary in whether they are open source; the Linux OS and most distributions based off it are open-source, whereas Windows and macOS are examples of proprietary OSs.
Multi-tasking and multi-user OSs
A multi-tasking OS allows more than one program to run at the same time in a computer. Users will be able to:
- do multiple tasks at the same time;
- switch between different active applications; and
- transfer data from one application to another.
A multi-user OS allows multiple users concurrently logging into the computer. The OS will need to handle:
- fair treatment of users with similar privileges;
- the issuance of priority to superusers;
- the privacy of users’ files and data sharing storages; and
- the protection of integrity of each user’s programs and data from:
- malicious attempts by others; or
- accidental mistakes from others.
Based on the definitions above:
| Operating System | Is a multi-user OS? | Is a multi-tasking OS? |
|---|---|---|
| Windows | No | Yes |
| Windows Server | Yes | Yes |
| macOS | Yes | Yes |
| UNIX | Yes | Yes |
| Linux | Yes | Yes |
How it works
Operating systems work with other components in a computer to fully make use of a computer’s resources and function well. These components include:
- the output system (BIOS);
- the operating system’s kernel and
- device drivers.
Functions
Generally has four important functions:
- file management — the handling of file-related activities (e.g., storage, retrieval, naming, and sharing);
- process management — the handling of the creation and destruction of processes and provision of mechanisms for synchronisation and communication across processes;
- memory management — the handling of the allocation and deallocation of memory space to programs; and
- device management — the handling of the management of I/O devices.