Linux is the most widely deployed operating system in history. It powers the servers that run the internet, the chips inside your phone, the navigation systems in your car, and the supercomputers doing climate modelling. It started as a message on Usenet from a bored Finnish student who just wanted a better terminal emulator.

1969: The roots — Unix

Linux did not appear from nowhere. Its design, philosophy, and most of its concepts come directly from Unix, an operating system developed at Bell Labs starting in 1969 by Ken Thompson, Dennis Ritchie, and others.

Unix established ideas that are still central to Linux today: everything is a file, small single-purpose tools that can be chained together, a hierarchical filesystem, multi-user access, and a clean separation between the kernel and user space. Most of the commands you run on Linux today (ls, grep, awk, sed, chmod) are direct descendants of Unix commands written in the 1970s.

Unix was proprietary and expensive, which created a long-running effort to build a free replacement.

1983: GNU begins

Richard Stallman, a programmer at MIT, resigned his position to dedicate himself to building a complete free Unix-like operating system. He called the project GNU (“GNU’s Not Unix”) and founded the Free Software Foundation (FSF) in 1985 to support it.

By the early 1990s, GNU had produced many of the essential components of a Unix system: the Bash shell, the GCC compiler, the Emacs editor, and dozens of core utilities. The one missing piece was a working kernel. GNU had a kernel project called Hurd, but it was not ready.

1991: The kernel appears

Linus Torvalds was a 21-year-old computer science student in Helsinki, using a PC running MINIX (a small Unix-like system designed for teaching). He found MINIX limiting and began writing his own kernel.

On August 25, 1991, he posted to the Usenet group comp.os.minix:

“Hello everybody out there using minix — I’m doing a (free) operating system (just a hobby, won’t be big and professional like gnu) for 386(486) AT clones.”

Version 0.01 followed in September 1991. It was about 10,000 lines of code and could only run on Intel 386 processors.

In early 1992, Torvalds changed the license from a custom no-commercial-use license to the GNU GPL. This was the decision that changed everything: with the GPL, companies could use and modify Linux freely as long as they contributed their changes back. Combined with the GNU tools that were already GPL-licensed, it created the complete, free GNU/Linux system.

1993-1994: The first distributions

Early Linux users had to compile everything themselves. Distributions emerged to package Linux into something installable:

• Slackware (1993): one of the oldest still-active distributions, created by Patrick Volkerding
• Debian (1993): founded by Ian Murdock, with a strong focus on freedom and community governance; the ancestor of Ubuntu, Mint, and hundreds of others
• Red Hat (1994): founded by Bob Young and Marc Ewing, would go on to build the dominant enterprise Linux business

In 1994, Linux kernel version 1.0 was released. It supported only single-processor x86 machines and had about 176,000 lines of code.

1995-2000: Linux goes professional

Several forces drove Linux into serious use during this period:

The internet explosion: Web servers needed a stable, cheap operating system. Linux filled this role perfectly. Apache (1995) became the dominant web server and ran almost exclusively on Linux.

Corporate investment: In 1999, Red Hat had one of the most successful tech IPOs of the dot-com era, demonstrating that companies could build profitable businesses around open source software.

Kernel growth: By 2000, the Linux kernel had grown to about 2 million lines of code and supported multiple processor architectures, symmetric multiprocessing, and most hardware in use at the time.

2003: The SCO lawsuit

The SCO Group filed a lawsuit claiming Linux contained Unix code that SCO owned, and sought over a billion dollars in damages from IBM (a major Linux contributor). The case rattled the industry for years before ultimately being dismissed. It established important legal precedents that protected Linux vendors and users, and IBM’s vigorous defence signalled that major corporations were fully committed to Linux.

2004-2008: Linux reaches desktops

Ubuntu launched in October 2004, founded by Mark Shuttleworth with the explicit goal of making Linux easy enough for ordinary users. Ubuntu shipped on a free CD (in the era before widespread broadband), had a professional installer, and focused on the full user experience. It became the dominant desktop Linux distribution and remains so today.

Android launched in 2008, built on the Linux kernel. This would go on to make Linux the most widely used OS in the world by user count, even though most Android users have no idea they are running Linux.

2010s: Linux dominates infrastructure

By the early 2010s, Linux had become the default choice for servers, cloud computing, and embedded systems:

• Cloud: Amazon Web Services, Google Cloud, and Microsoft Azure all run primarily on Linux
• Containers: Docker (2013) and Kubernetes (2014) are built on Linux kernel features (namespaces and cgroups)
• Supercomputers: since November 2017, all 500 of the world’s top supercomputers run Linux
• Smartphones: Android, running Linux, has over 70% global smartphone market share

2020s: Linux today

The Linux kernel has about 27 million lines of code (as of 2022) and receives contributions from thousands of developers at hundreds of companies. The top corporate contributors include Intel, AMD, Google, Meta, and Red Hat (now part of IBM). Microsoft, once famously hostile to Linux (Steve Ballmer called it a “cancer” in 2001), is now one of the largest corporate contributors to the Linux kernel.

Key milestones of the recent era:

• Microsoft WSL2 (2019): Linux runs natively inside Windows via the Windows Subsystem for Linux, allowing developers to use Linux tools on Windows machines
• Apple Silicon Macs: Asahi Linux (2022) brought Linux to Apple M1/M2 hardware
• Steam Deck (2022): Valve shipped a Linux-based handheld gaming PC to millions of consumers, using a custom Arch-based distribution called SteamOS
• Kernel 6.x: the 6.0 kernel was released in 2022, continuing the pace of roughly 8-10 kernel releases per year

The development model

Linux kernel development operates on a roughly 9-10 week release cycle. Torvalds manages the merge window (2 weeks), during which new code is accepted. The remaining weeks are spent stabilising for release. The kernel has thousands of active contributors; a typical release contains contributions from over 1,000 developers at over 200 companies.

# See your kernel version
uname -r

# See kernel build information
uname -a

# See the kernel release date
uname -v

Frequently Asked Questions

Who created Linux and when?

Linux was created by Linus Torvalds, a Finnish computer science student at the University of Helsinki. He began writing it in 1991 and announced the project in a now-famous post to the Usenet group comp.os.minix on August 25, 1991, describing it as “just a hobby, won’t be big and professional like gnu.” The first public version (0.01) was released on September 17, 1991. Torvalds continues to lead kernel development today as the principal maintainer of the Linux kernel.

What is the difference between Linux and GNU/Linux?

The Linux kernel is just the core of the operating system — it manages hardware, processes, and memory, but it does not include the user-facing tools needed to actually use a computer. The GNU Project, started by Richard Stallman in 1983, had been building a free Unix-like operating system and had created most of the essential tools (shell, compiler, text editor, utilities) but lacked a working kernel. When Torvalds released the Linux kernel, it was combined with GNU tools to create a complete, usable system. Stallman and the Free Software Foundation argue the full system should be called GNU/Linux; most people shorten it to Linux.

What is a Linux distribution?

A Linux distribution (distro) is a complete operating system built around the Linux kernel. It packages the kernel with a package manager, init system, desktop environment (optionally), pre-selected software, and configuration tools. Different distributions make different choices: Debian prioritises stability and freedom; Ubuntu prioritises ease of use; Arch prioritises user control and cutting-edge packages; Fedora prioritises being current while remaining stable. There are hundreds of active distributions, but most modern ones are derived from Debian, Red Hat, or Arch.

What was MINIX and why did it matter for Linux?

MINIX was a minimal Unix-like operating system created by professor Andrew Tanenbaum in 1987 for teaching operating system concepts. It was small, well-documented, and inspired Linus Torvalds, who used it on his own computer and studied it while learning OS development. When Torvalds wanted features that MINIX lacked, he began writing his own kernel. His original announcement was posted to comp.os.minix, addressing the community of MINIX users. MINIX and Linux later became the subject of a famous public debate between Tanenbaum and Torvalds about monolithic vs microkernel architecture.

What license does Linux use?

The Linux kernel is licensed under the GNU General Public License version 2 (GPLv2). This means anyone can use, study, modify, and distribute the kernel, but modifications to the kernel itself must also be released under the same license (this is called copyleft). Torvalds changed from an initial no-commercial-use license to the GPL in 1992, a decision he later described as the best he ever made, because it encouraged companies to contribute back improvements rather than keeping them proprietary. Kernel modules written for Linux can be proprietary (Nvidia drivers are a notable example), which has been a source of ongoing controversy.

What is the Linux Foundation?

The Linux Foundation is a non-profit organisation founded in 2000 (originally as Open Source Development Labs) that supports the development of Linux and many other open source projects. It employs Linus Torvalds and other key kernel developers to work on Linux full-time, funded by corporate members including Google, Microsoft, Intel, IBM, and hundreds of other companies. The Linux Foundation also hosts major collaborative projects beyond the kernel, including Kubernetes, Node.js, Let’s Encrypt, and Hyperledger.