Types of OS

Business client
- An OS designed to work as a client in centrally managed business domain networks.
Network Operating System (NOS)
- An OS designed to run servers in business networks.
Home client
- An OS designed to work as a standalone machine or in a workgroup network in a home or small office
Cell phone (smartphone)/Tablet
- An OS designed to work with a handheld portable device. This type of OS must have a touch-operated interface

Windows

Windows 10 and 11 support:
- business workstation
- home use
Windows Server 2019 and 2022
- used for NOSs
- share underlying code and desktop interface as client versions
Windows 11 requires a CPU/motherboard with support for TPM v2

UNIX is a trademark for a family of operating systems originally developed at Bell Laboratories in the late 1960s
use a kernel/shell architecture
- kernel is low-level code that mediates access to system resources
- interchangeable shells run on the kernel to provide the user interface
UNIX is portable to a large range of hardware platforms

fully open-sourced OS kernel, derived from UNIX
bundled with shell, command interpreter, desktop environment, app packages
many different linux distributions
distros can use different licensing and support options
2 release models:
- standard release model uses versioning
- rolling release model means updates are delivered once distro owner considers them to be stable
  - no distinction between versions
can be used as desktop or server OS

derived from Linux via an open-source OS called Chromium
Chrome OS is proprietary
developed by Google to run on specific laptop hardware
designed for budget and education markets
primarily developed to use web applications
- software hosted on a server on internet
does not need to be powerful, as server does most of the processing
minimal environment compared to Windows
also has packaged apps available for offline use

iOS is the operating system for Apple’s iPhone smartphone and original models of the iPad tablet
derived from UNIX and developed as a closed-source operating system
new versions released about every year

developed from iOS to support the functionality of the latest iPad models (2019 and up)
advantage of iPadOS over iOS is better support for multitasking (using more than one app at once) and the Apple Pencil stylus device
Versions released in parallel with iOS

Android is a smartphone/tablet OS developed by the Open Handset Alliance, primarily driven by Google
open-source OS, based on Linux
Because handset vendors produce their own editions of Android, device compatibility for new versions is more mixed compared with iOS
End-of-life policies and update restrictions are determined by the handset vendor