Table of Contents
A Look Inside Linux series
A series of short (~5 minutes) topics on how Linux works and how to make it work the way you want it to, which I present during the weekly sessions of the Linux User Net. The target audience is Hams who are new to Linux and want to know more about it, as well as experienced Linux users who can learn more about their chosen operating system. These are my notes for the presentations. (Russ, KC7MM)
2. What is a Linux distribution?
(Jan. 17, 2022)
Introduction
If you're planning to install Linux on a computer, you most likely are evaluating various distributions to determine which one would work best for you. That begs a few questions:
- What is a Linux "distribution"?
- What distinguishes distributions from each other?
- Why would you choose one distribution over another?
We'll address each of these questions in turn.
What is a Linux "distribution"?
NOTE: In common usage, the term distribution often is shortened to distro.
As applied to Linux, the term distribution describes a complete Linux system, ready to be installed and used. The creator of the distro does the following:
- Selects a version of the Linux kernel, perhaps compiling it to meet the specific goals of the distro.
- Selects application software that will be available to users of the system.
- Provides administrative tools for configuring and maintaining the system.
- Packages all the software for distribution to potential users.
- Makes the packaged distro available (usually on-line) for users to obtain for installation and use.
When you download a distribution and install it, you expect to have a complete, working Linux system that you can begin to use immediately. Exactly what you can do with that system depends on decisions made by its creators when they designed and assembled the distro – which leads us to the next question.
What distinguishes distributions from each other?
A distro is designed for a purpose
Linux is a general-purpose operating system. That is, it can be used to accomplish a wide variety of automated tasks. The object of making a Linux distribution is to assemble a system that has all the tools it needs to meet a specific purpose: serving Web pages, perhaps, or streaming audio, or providing a desktop environment for users. Given the fact that anyone can create a distro, the purposes they are designed to serve are as varied as the desires of their creators.
Software depends on the purpose
In order to serve a desired purpose, the distro is designed to include the software components that are appropriate to it. Web servers, firewalls, databases, Web browser, and the like, all perform specific tasks, and so might or might not be included in a distro depending on how well they fit its design goals.
Administration and maintenance tools may vary
Most distributions organize software components into pre-compiled packages that are stored in an on-line repository. An application called a package manager is provided for the user to install and maintain the system's software. How this scheme is implemented can vary between distributions.
In addition, methods and tools for system configuration can differ. There currently is heated debate between proponents of the older AT&T SysV init system and the newer Systemd from Red Hat, which has resulted in distros coming into being so as to use one or the other.
Why would you choose one distribution over another?
What is your purpose?
The most obvious answer here is that you want to select a distribution that is designed to do the things that you need it to do. If you need a Web server, there's no point in installing a fully-graphical desktop system. OTOH, if you want to watch streaming video, a Web server won't be up to the task, and you'll need that desktop.
It should be noted that, with some distros, it's possible to customize your system for a specific task during the installation process, simply by choosing general classes of software to install. The Debian installer, for example, lets you select between a bare-bones base install, pre-configured basic sever, and various desktop environments.
A learning curve
Beyond that, there is the matter of system administration to consider. It can be convenient to go with a distro that uses familiar administration and package management tools.
Finally
The Linux universe is very large. I haven't even mentioned its extremes: tiny embedded systems and enormous supercomputers. It's unlikely that you'll build a supercomputer, but many Hams are working with embedded Linux systems. For example, the AREDN mesh networking firmware is a version of Linux that runs on commercial WiFi routers.
A good source of information on the many and varied Linux distros is the DistroWatch Web site.
That's the high-level view of Linux distributions. I'll talk more about how they can be used to build the computer system that you need at another time.
