25 Years of Linux: What a Long, Strange Trip It’s Been

Happy Birthday, Linux! You’re 25!

When Linux was born on Aug. 25, 1991, it was little more than a hobby for then-21-year-old Linus Torvalds. Today the Linux community is estimated to be upwards of 86 million users strong. It has become the backbone of large enterprises, and it is installed in government systems and embedded in devices worldwide.

The Linux operating system started out as an alternative to other platform architectures used on mainframes and enterprise back-ends. It has grown into a major mainstream computing platform for small businesses through large companies’ server operations and has made inroads into consumer computing.

Linux has been ported to more hardware platforms than any other operating system, thanks to the popularity of the Linux-based Android operating system, noted Meike Chabowski, documentation strategist at Suse.

“Today, Linux has the largest installed base of all general-purpose operating systems worldwide. Linux is also the leading operating system on servers of any sort and of 99.4 percent of the top 500 supercomputers,” he told LinuxInsider. “Also, you find embedded Linux in a huge quantity of devices and machines — built into cars, network routers, facility automation controls, entertainment equipment, and medical equipment such as X-rays.”

Some people do not even know they are using it. Linux is everywhere, Chabowski said.

Full of Surprises

Early Linux was a revolutionary idea. It provided some conveniences not available to the Minix and Unix operating systems used at the university where Suse President of Engineering Ralf Flaxa studied.

One big plus was that he could run it himself on his PC at home, he told LinuxInsider.

What also surprised Flaxa was how quickly Linux evolved and improved and how much it could do in such a short period of time.

“For example, at the very beginning, you were able to multiplex your screen — meaning with a key combination, you could switch to a second or third terminal,” he noted.

“This was a brilliant idea and feature, especially at the time. There was no graphical environment with multiple windows yet,” Flaxa said.

The surprises did not stop there.

“I started out with Linux as a pure hobby and because I wanted and needed it for my computer science studies,” Flaxa recalled. “The moment I realized that I could actually turn my hobby into my job was for me personally the biggest Linux milestone.”

Gerald Pfeifer, senior director of products and technology programs at Suse, cited the ease of swapping out hardware as a major benefit of Linux, as that was not the case with other operating systems.

“You can exchange any piece of hardware and an existing Linux installation will still work just fine,” he told LinuxInsider.

Linux’s open philosophy was the biggest surprise with the new computing technology, said SUSE’s Chabowski. The philosophy of open and free source code impressed him from the start, “but what surprised me most and still does fascinate me today about Linux is that its model of joint and worldwide development worked and still works.”

Linux at the Floodgates

Linux was a “good enough” operating system with the right price for a startup — free — recalled Cloud Foundry CEO Sam Ramji, who worked with Linux for the first time in 2000 when his company built the online digital photo-developing service Ofoto.

“We used our knowledge instead of paying for Solaris licenses,” he told LinuxInsider. “The leap from copycat to innovator was not something I had imagined, but by the mid-2000s, new features were coming to Linux that did not exist anywhere else — things like filesystems and cgroups.”

Awareness of Linux in the enterprise was nonexistent 25 years ago when Ramji was an undergrad at the University of California, San Diego. Solaris, MacOS, and Windows dominated.

Even by the late 1990s, Linux could not provide the support and predictability needed in an enterprise setting. Companies using Linux had to build their own skill sets based on a free distribution or build their own in-house version. Adoption risk was high.

All that changed in the early 2000s when Wall Street banks demanded Linux support for their enterprise application servers.

“That moment broke down resistance to Linux in big IT vendors like BEA, IBM, and Oracle. That hole in the dam was the start of a flood,” said Ramji. Today, Linux is the home of operating system innovation.”

Changing World

Installing Linux was far from easy in the early days, according to Aporeto Virtualization Expert Stefano Stabellini, who has been a Linux user and open-source advocate since the 1990s.

“It was very difficult to explain open source to people and companies back when I started with Linux in the ’90s. They did not understand it. They thought that open source was unsustainable, and Linux was niche and hobbyist,” he told LinuxInsider.

Now everything has changed. Every company has an open source strategy now.

“Microsoft was the biggest foe and now is a strong ally. Linux is the most widely adopted operating system of all time. It is known as the kernel that powers smartphones and light bulbs as well as supercomputers — that is the opposite of niche,” Stabellini said.

Secret Glue

The Linux kernel community deserves a large measure of credit for Linux being everywhere, according to Stabellini. The Linux kernel is a vast community of very different people. Many work for competing companies. They have expertise in different areas, different world views, and different modus operandi.

“It is surprising how remarkably dissimilar they can be, but their first and foremost goal is to progress Linux. It’s the glue that holds it all together,” Stabellini said.

As for the industry as a whole, two milestone achievements thrust Linux toward universal adoption, he said. One was the introduction of cgroups, which paved the way for the Linux containers of today. Another was development of the device tree for the ARM architecture, which made the growth of ARM boards in Linux sustainable.

Risk Factor

Using Linux in the early days was a major risk for early enterprise adopters. Too many unknowns clouded its sustainability potential.

“In the early days, I think the biggest challenge for enterprises using Linux was risk. Enterprises were not sure the project would continue. They did not know if it would support their hardware. They were not clear on the best way to maintain updates, and the expertise was hard to find,” said Matt Hicks, vice president software engineering at Red Hat.

“However, the desire for a more open standard beyond the Unix distributions was strong, and it drove many to undertake those risks,” he told LinuxInsider.

Today’s Linux landscape looks much different. Linux is at the core of almost all technology innovation. The ecosystem surrounding it is massive, and talent abounds. In a very real sense, Linux has become the safe bet for those who are using technology as a core part of their business, Hicks pointed out.

The release of the Linux 2.6 kernel on Dec. 17, 2003, along with the publication of Linux Kernel Development by Robert Love, are two milestones that changed Linux forever, Hicks said. “Despite having worked with Linux for years prior, that was the point at which I realized that Linux had a momentum that could change the industry.”

Transiting Transition

Perhaps the biggest challenge for Linux was aligning the open source movement with the openness of a new operating system that broke all the rules, suggested Fedora Project Leader Matthew Miller. The open culture and wider free and open source movement grew up with Linux.

“Obviously, the Free Software Foundation was working for years before Linux came around, but Linux was really the catalyst for something big — a whole movement,” Miller told LinuxInsider.

In the beginning, Linux distributions were largely hobbyist projects. Even the business-oriented ones with greater aspirations were basically that way, he noted.

“Don’t get me wrong. They were impressive work, but they were far from meeting enterprise or large installation needs. Security, in particular, was horrible, with no real preemptive lockdown. System accounts with no password were the norm, and every possible service was usually enabled out of the box. And there was not even a good model for updates — even for security issues,” Miller recalled.

Regardless, the Linux movement fascinated people. Linux installs grew from the inside as individual groups kept installing them. Eventually, it became a sort of “If you can’t beat ’em, join ’em,” he said.

“I think Red Hat Enterprise Linux came along just at the right time, focusing on solving these problems — and perhaps more importantly, offering certifications and guarantees that open source was safe to use, Miller observed.

New Default

In the early 1990s, Linux in the enterprise was typically geared toward Web servers, FTP, and smaller-scale applications. Linux was much less about workloads. Most enterprises in the ’90s had mixes of hardware with a lot of Sun and SGI, as well as applications that were very particular about the hardware they ran on, such as Oracle, noted Dave Rosenberg, senior vice president for strategy and ops at The Linux Foundation.

Linux in the enterprise is much different today. As the ’90s progressed into the 2000s, commodity servers became the norm, and Linux had the best stability and largest ecosystem of developers. That was and still is very appealing for enterprises.

“What has changed is that Linux has become the default over the last 10 years. There is no longer the question, ‘ Should I use Solaris, or should I buy an SGI?’ Linux is already assumed to be the de facto OS standard,” Rosenberg told LinuxInsider.

It is hard to point to another technology that has changed the technical and business landscape as much as Linux has.

“It is important to note that even with the disruption that was felt by many companies, such as Sun and Microsoft, that Linux is a massive, massive net positive for everyone.,” Rosenberg said.

New Possibilities

Linux proved its resilience after 25 years of being free and open. Today’s new approaches and innovations are possible because of Linux, and not in spite of it, according to Gunnar Hellekson, director of product management for Red Hat Enterprise Virtualization and Red Hat Enterprise Linux.

“Linux’s central challenge and strength have always been its relatively fragmented ecosystem when compared with proprietary alternatives,” he told LinuxInsider. Choice and options are wonderful for innovation but do not make things easier operationally.”

For example, consolidating packaging systems like RPM and DEB was a monumental and messy effort. Hopefully, containers will offer the tools to begin harmonizing the packaging mechanisms for the sake of Linux developers, Hellekson said.

“If we take a step back, Linux’s success has inspired an entire generation of software developers to work in open source communities while simultaneously making that work possible on open source platforms,” he added.

Without Linux, today’s computer users would still be hobbyists distributing shareware for Windows PCs. Instead, there is a completely different IT ecosystem, Hellekson noted — one that “is much more inclusive, much more expansive and much more effective.”