What is Linux? A Closer Look at the Universal Operating System

Linux is an operating system (OS) such as Windows or macOS. An OS is system software that runs on a computer. 

The OS manages the computer’s hardware and software resources and provides services to programs running on the computer. The OS is an interface or a layer between the applications running on the computer and the hardware. Users start and stop most applications. Linux starts when the computer turns on and stops when the computer turns off.

Windows and macOS are proprietary software systems. Linux is an Open Source operating system. The OpenSource.org license applies to open-source software. It grants everyone the right to use, study, change, and distribute it to anyone for any purpose. Proprietary software, also known as Closed Source software, has commercial licenses. It does not share the source code, and the user does not have access to look at or change the program.

The mascot of Linux is a penguin called TUX. The name TUX derives from Torvalds UNIX. The penguin often reflects the Linux version or the system it supports. 

Many devices containing a computer run the Linux OS. These include cell phones, video game devices, laptops, personal computers, web servers and supercomputers, and dedicated devices such as routers.

Linux History

Let’s see how it all started and review some important milestones in Linux history.

The modern computer era began in the 1960s. It was the start of computers with a mouse and a graphical user interface (GUI). They no longer specialized computers for scientists and mathematics. The new computers were more accessible to the public.

In late 1970 Bell Labs released the first version of Unix. It was re-written in C to make it portable. Universities and corporations began to adopt, copy and change this new portable version.

The 1970s and 1980s saw the development and distribution of many versions of Unix. AT&T announced Unix System V. In 1982, Sun Microsystems created its own version of Unix called SunOS (renamed later as Solaris). Hewlett-Packard implemented HP-UX and IBM developed its own Unix OS called AIX. These versions of Unix were proprietary, and changing the source code was prohibited.

As the market grew, manufacturers stopped distributing source code with their software to prevent it from use on competitors’ computers. They began using copyright and restrictive software licenses to limit copying and redistribution. This shift toward more proprietary software triggered the US Copyright Act of 1976.

This movement toward proprietary software triggered Richard Stallman to launch the GNU Project in September 1983. The goal was to create a Unix-like operating system composed entirely of free software. Richard quit his job at the MIT Artificial Intelligence (AI) Laboratory in January 1984 to work on the GNU Project full time. The name of the project is a recursive acronym for GNU’s Not Unix. You pronounce it as a single syllable with a hard g.

The primary and continuing goal of GNU is to offer 100% free software. This is not a reference to the price of the software. Free refers to the ability to (1) to run the program, (2) study and change the program source code, (3) redistribute exact copies free or for a fee, and (4) to distribute modified versions of the source code.

The GNU General Public License (GNU GPL or GPL) covers GNU programs. GPL is a software license used with free software. It guarantees end-users the freedom to run, study, share, and change the software.

In 1987 Andrew S. Tanenbaum released MINIX, a Unix-like system intended for academic use. MINIX intended to showcase the principles conveyed in his textbook Operating Systems: Design and Implementation. While the source code was available, MINIX applied restrictions to modification and distribution.

In 1991, while a student at the University of Helsinki, Linus Torvalds developed a new Unix kernel. Linus developed the kernel for the hardware he was using independent of any operating system. Linus wanted to use the capabilities of his new PC with an 80386 processor. He used the GNU C compiler to build the OS on a MINIX. Today the OS is the Linux kernel. It runs on all distributions of the Linux Operating System (abbreviated as distros). 

Developers use C and Assembly languages with the Linux kernel. It has over 27 million lines of code. Linux® is the registered trademark of Linus Torvalds in the U.S., Germany, EU, and Japan. 

Linux Distributions and Desktop Environments

A Linux distro is an operating system based on the Linux kernel and a package management system. The package management system is a collection of tools used to manage the software installed on the computer in a consistent manner. A typical distro includes the Linux kernel, GNU components, tools, and libraries, a window system, w windows manager, and a Desktop Environment (DE). The most common window system is the X Window System.

Most of the software included in the Linux distro is free and open-source. Included are both the source code and compiled binaries. Some software in the distro may be proprietary binaries not available in an open-source format, like device drivers. Almost one thousand different Linux distros exist.

A DE is a collection of components that provide a common graphical user interface (GUI). The DE includes visual elements such as toolbars, icons, menus, and desktop widgets. The existence of so many DE’s reflects the rich nature of open source systems. The choice allows the user to select a GUI that meets their needs.

DE Environment	Description
Cinnamon	Cinnamon came from GNOME3 and receives favorable reviews because it is easy to use and learn. Cinnamon is the default interface for the Linux Mint distro.
GNOME3	Easy to use, clean, and modern. GNOME3 is the default DE for many Linux distros.
KDE	Customizable DE with moderate use of system resources.
LXDE	The Lightweight X11 Desktop Environment (LXDE) is fast and uses few system resources. LXDE is the default DE for Knoppix and is often used on netbooks and system on a chip computer.
MATE	MATE came from GNOME2 and provides an intuitive and attractive DE. MATE is under active development.
Xfce	A lightweight DE, Xfce is fast, low on resource usage, visually appealing, and user friendly.

Users download Linux distros online. The website DistroWatch.com provides news, rankings, and other information about Linux distributions. Users can research every version of Linux and find links to download the distro of their choice. The site includes Open Source and Free Software. Commercial options are available for a fee. Non-commercial, community-supported options are free.

Volunteers of services and money maintain community distros. Companies with commercial distros compete with Windows and OS X distros. There was a time when members of community distributions were purists that viewed commercial distro’s as stolen with corrupted ideals and business interests. Commercial distributors saw community distros as naive. While the differences are minor, many companies back both commercial and community distros, but the distinction still holds true. It is important to remember there are exceptions to the general differences.

It is worth noting that there are special-purpose Linux distros. OpenWRT targets embedded devices such as Routers. Raspberry Pi OS is a Debian-based OS for Raspberry Pi computers. Android is a modified version of the Linux kernel designed for touchscreen devices.

What are the benefits of using Linux? 

1. Linux is secure and private

“Security through obscurity” is a catch-phrase used with Windows and OS X. The idea is that these systems are secure because the source code is not exposed. “Linus’ Law” holds that given enough eyeballs, all bugs are shallow. That means the larger the group of developers and testers, the faster users will catch and fix flaws.

Linux systems rarely run anti-virus programs. The permissions model is more secure, with the default user given minimal permissions. Given a large number of Linux distributions, it is not easy to develop a virus that will work across all versions of Linux.

If a Linux distro adds a data collection module as Ubuntu did, users will shout is loud and clear. The open nature of the Linux community ensures that someone will see the development and flag it on Linux forums. The Ubuntu installation provided an opt-out option. It only targeted system metrics designed to improve the product. But the introduction of the Ubuntu collectl module sent shockwaves through the community.

2. Linux is free

Most Linux distros are available for free. Having something both very good and free is one of the best things one could expect.

3. Linux is reliable and a top performer

Over time Windows installations become sluggish. The user needs to initialize the computer needs and reinstall the OS. Installation of new software often requires a reboot. Neither of these cases applies to Linux installations, providing a more reliable and steady computing environment.

Linux is also the OS of choice for many large corporations. Amazon, Netflix, eBay, PayPal, and Facebook are some excellent internet examples. Stock exchanges have migrated to Linux servers for the security and speed it offers. Even SpaceX uses Linux for Starlink satellites.

In supercomputing, Linux dominates. According to TOP500, Linux OS runs all 500 of the world’s fastest supercomputers. TOP500 has been tracking the top 500 high-performance computers worldwide since 1986.

4. Linux is good for old hardware

As operating systems evolve, so too do the minimum computer requirements. Hardware is obsolete at a faster pace by the increased frequency of new OS releases.

Lightweight Linux distros are perfect for reviving these computers. MX Linux, Puppy Linux, or Pop!_OS are such distributions. These distros have minimal desktop clutter and low resource usage. Puppy Linux is a great example. Puppy will run smooth and fast with as little as a 333Mhz processor and 256MB of RAM. 

5. Linux is easier to install and use than ever

Freeware does not mean you will have to wrestle the installation to the ground! You can install a modern Linux distribution in less than 30 minutes. 

A great way to experience Linux is to download a distro to a USB drive and boot the computer. You can use all the apps and tools and access the web without committing to a hard-drive installation.

7. Education

Given the free (price) software, Linux is a fantastic educational tool available to all. Many open-source Linux programs are available that support a broad range of topics.

Let’s have a look at some of these interesting fields of study!

Astronomy 

Celestia is a free space simulator exploring the universe in three dimensions. Stellarium is a planetarium software product that displays exactly what you see when you look up at the stars.

Chemistry

Avogadro is an advanced molecular editor and visualizer. Gabedit is a GUI that works with many computational chemistry packages. Gabedit displays calculation results and allows users to sketch and examine molecules in 3D. 

Biology

EMBOSS is the European Molecular Biology Open Software Suite. It is a fantastic open-source program for the large and active molecular biology user community. ROOT enables sound scientific analysis and visualization of large amounts of data. Users have stored over 1 exabyte of data in ROOT files today.

8. Support

There is strong community support for Linux over the Internet. There are many forums online to ask questions and get help. The most complete might be the Linux community itself – the Linux Org forum.

Conclusion

Linux is an ideal Operating System for both beginners and experienced users. Compared to other operations systems, it has only one master, and that is you!

Enroll in my Master Linux Administration: The Complete Linux Bootcamp class. We’ll do a deep dive into many aspects of Linux. By the end of the course, you will be a Linux superuser and a qualified Linux Administrator.