What is Linux?

In this article, you will learn what Linux is, where Linux came from, what a Linux distribution is and some of the reasons that Linux is favored for certain applications and projects over other operating systems.

Linux is an Operating System

First and foremost, Linux is an operating system. An operating system is simply a collection of software that manages hardware resources and provides an environment where applications can run. The operating system allows applications to store information, send documents to printers, interact with users and other things.

Linux is a Kernel

Linux is also a kernel. Typically, when the term “Linux” is used, it refers to the Linux operating system as a whole. However, it can refer to just the Linux kernel as well.  The Linux kernel is the core or the heart of the operating system. It’s the layer that sits between the hardware and applications. Said another way, it’s the intermediary between software and hardware. However, to have a useful operating system, you need other components in addition to the kernel. These components can include system libraries, graphical user interfaces, email utilities, web browsers and other programs.

Linux Was Created by Linus Torvalds

Linus Torvalds created Linux when he was a student at the University of Helsinki, studying computer science. In early 1991 he purchased an IBM-compatible personal computer that came with the MS-DOS operating system. Linus wasn’t satisfied with MS-DOS and wanted to use a UNIX operating system like he was accustomed to at the University.  When he set out to obtain a copy of UNIX for his personal use, he found that the least expensive UNIX he could buy was about $5,000 USD. Driven by the desire to run a UNIX-like operating system on his personal computer, he set out to create Linux.  Linus and over 100 developers worked on Linux over the next couple of years and in March 1994, version 1.0 of the Linux kernel was released.

Linux is Open Source Software

Linux is open source software. This means that anyone can use, copy, study and change the software in any way they chose so long as the source code is openly shared with others. To date, thousands of people have made improvements to Linux.  With Linux being free and open source software, it has led to the rise of Linux distributions.  In every case, the source code is free, but in some cases, the distribution is not free – the binaries, the compiled code is not free. For example, you have to pay a license in order to run Red Hat Enterprise Linux. However, Red Hat releases their source code for anyone to download.

Linux Is Not Unix, but It Is a Unix-Like Operating System

Again, Linux is not a UNIX-derivative. It was written from scratch. However, many of the commands that are found on Linux are also found in UNIX. If you have any experience on UNIX systems, you’re going to feel right at home on a Linux system.

Linux Distro = Linux Kernel + Additional Software

A Linux distribution is the Linux kernel and a collection of software that, together, create an operating system. Each distribution has its own goals and areas of focus. Your choice of distribution will depend on what you’re trying to accomplish. There are distributions that are commercial. These commercial Linux distributions are backed by corporations, and you can buy support from them. There are non-commercial Linux distributions. These are maintained by a community of volunteers. You have Linux distributions that are designed for server use, others that are designed for desktop use, some that are focus on research and science. There are others that are focused on multimedia production. There are literally hundreds of Linux distributions.

DistroWatch.com is a great website to learn about all the available Linux distributions. “Distro” is short for distribution. Here are some popular Linux distributions:

Linux Open Source Code
  • RedHat Enterprise Linux (RHEL)
  • Fedora
  • Ubuntu
  • Debian
  • SuSE Linux Enterprise Server (SLES)
  • OpenSuSE
  • Linux Mint
  • CentOS Stream
  • Rocky Linux
  • AlmaLinux

Again, there are a hundred of Linux distros. These are just a few of the most popular Linux distributions. To get an idea of exactly what’s available, go to DistroWatch.com.

Why Would You Want to Run Linux?

Linux runs on many hardware platforms, from dedicated networking devices to phones to personal computers and even super computers. Proprietary UNIX operating systems typically only run on their hardware from their company. For example, HP-UX only runs on HP servers, AIX only runs on IBM servers. Linux can run on HP, IBM and other servers. Linux was developed on PC hardware using Intel processors. Over time, Linux has been ported to more hardware platforms than any other operating system.

Linux is Lightweight and Stable

The small footprint of Linux allows it to run on older hardware or on embedded systems. Also, Linux is known for being stable, reliable and secure. This makes it a great source for servers that need to continuously run without downtime.

Linux has traditionally been used for server applications. Linux can be used to host websites, act as file servers and even run database software. Linux doesn’t have to be used as a server though.  Many people find Linux to be a good everyday operating system that they use on their personal desktops.

Linux is Free

Not only is the source code freely available, but you can run Linux on your hardware without having to be pay a licensing fee in many cases. However, if your business depends on servers that are running Linux, having a commercial Linux distribution which you pay for and having someone that can provide support can be well worth your while.

Linux is typically not as costly as the proprietary UNIX operating systems. Linux is also free in the sense that you can use it for any purpose, and you can modify it to fit your needs if you so desire. There are also many free software applications that run on Linux. Many of these free applications were written with Linux in mind.

Linux, in Summary

Let’s recap what we’ve gone over in this article. First, we learned that Linux is an operating system. When someone says the word “Linux” without a qualifier, more than likely they are talking about the entire operating system. However, Linux is also a kernel. When people speak of the Linux kernel, they are typically specific and say “the Linux kernel.”

Linux, being the operating system, is the intermediary between hardware and software. Linux distributions are implementations of Linux. Each Linux distribution has a different goal and a slightly different focus. Your choice of distribution will be driven by the goal you are trying to accomplish.