less_retarded_wiki

Operating System

Operating System (OS) is normally a hugely complex program that's typically installed before any other program and serves as a platform for running other programs as well as managing resources (CPU usage, RAM, files, network, ...) and offering services and interfaces for humans and programs.

There is a nice CC0 wiki for OS development at https://wiki.osdev.org/.

From programmer's point of view a serious OS is one of the most difficult pieces of software one can pursue to develop. The task involves an enormous amount of low-level programming, development of own tools from scratch and requires deep and detailed knowledge of all components of a computer, of established standards as well as many theoretical subjects such as compiler design.

An OS, as a software, consists of two main parts:

• kernel: The base/core of the system, running in the most privileged mode, offering an environment for user applications.
• userland (applications): The set of programs running on top of the kernel. These run in lower-privileged mode and use the services offered by the kernel via so called system calls.

For example in GNU/Linux, Linux is the kernel and GNU is the userland.

Attributes/Features

TODO

Notable Operating Systems

Below are some of the most notable OSes.

• Android
• BSD systems such as OpenBSD and freeBSD: Unix-like OSes
• Collapse OS
• DOS, FreeDOS
• GNU/Linux systems encompassing many distributions
• Inferno: OS in the style of Plan 9
• MacOS
• Minix
• Plan 9: research OS, continuing the ideas of Unix
• ReactOS
• Replicant
• Solaris
• TempleOS: simple meme OS written by a Terry Davis
• Unix
• Windows: very bad proprietary capitalist OS
• 9front: OS based on Plan 9

All content available under CC0 1.0 (public domain). Send comments and corrections to drummyfish at disroot dot org.