Linux Fundamentals: Kernel, Free Software, and Ecosystem

Understanding Linux: Kernel, Free Software, and Distributions

Like any operating system, Linux is a combination of a main program, or kernel, and a series of added tools and libraries that enable its use. It possesses two distinguishing features:

• It is free software.
• It is distributed with its source code.

Most programs and libraries added to the Linux kernel to create a more user-friendly system have been developed by the GNU Project. For this reason, some people refer to Linux as GNU/Linux, clarifying that the operating system comprises not only the kernel but also all those programs and libraries.

Key Concepts Defined

Free Software

Software that can be used, copied, studied, modified, and redistributed freely.

Source Code

A set of text lines that follow the syntax of a programming language, understandable to humans. To make changes to a program, it is imperative to have access to its source code.

Kernel (Núcleo)

The main or central part of an operating system that manages resources, secures access to computer hardware, and determines which program can use the hardware at a particular time and for how long.

The Origin of Linux

In 1991, Linus Torvalds, a student at the University of Helsinki, began working (initially for entertainment) on creating a basic source code. When perfected, this became the first kernel of what is now known as Linux. The first official version of Linux was announced in October 1991.

Tux: The Linux Mascot

In May 1996, the Linux kernel mascot, named Tux, was created and is represented by a penguin. There are two assumptions regarding the mascot's meaning: one is that it represents Linus Torvalds' name, and the other refers to the word tux, an abbreviation of 'tuxedo,' the formal suit apparently worn by penguins. The mascot's author was Larry Ewing, and it can be modified provided his authorship is acknowledged.

Linux Distributions Explained

To facilitate Linux usage, distributions (sometimes informally called 'distros') have been created. These distributions include the Linux kernel and GNU tools, bundle multiple applications, and often provide tools for installing, configuring the system, and managing additional software.

Popular Linux Distributions

Among the wide variety of distributions available, some of the most used include:

• Debian
• Red Hat
• Fedora
• SuSE
• Slackware
• Gentoo
• Ubuntu

Spanish Regional Linux Adaptations

In Spain, various Autonomous Communities have developed their own Linux adaptations. The pioneer was Extremadura in 2002 with the creation of GNU/Linex. Other notable adaptations include:

• Molinux in Castilla-La Mancha
• Max in the Community of Madrid
• Guadalinex in Andalusia
• Linkat in Catalonia
• Lliurex in the Valencian Community
• Melinux in Melilla
• mEDUXa in the Canary Islands
• Áuqustux in Aragon
• Trisquel in Galicia