A Brief History of Open Source

The concept of open source software (OSS) – where the source code is made freely available for anyone to use, modify, and distribute – has become a driving force in the world of technology and beyond. Today, open source powers everything from the web servers running most of the internet (Apache, Nginx) to the smartphones in billions of pockets worldwide (Android). Major companies like Google, Facebook and Amazon rely heavily on open source components. By some estimates, 98% of enterprises use open source in some way.

But it wasn‘t always this way. The open source movement as we know it today began to take shape in the 1980s and then accelerated dramatically in the late 1990s and 2000s as the internet took off. In this in-depth article, we‘ll trace the fascinating history of open source from its philosophical origins to its current ubiquity. We‘ll examine the key people, projects and trends that shaped its evolution, the challenges the open source community has grappled with, and where this transformational idea might be headed in the future.

Free Software Sets the Stage

The notion of collaboratively developing software with freely shared source code actually dates back to the early days of computing in the 1950s and 60s. User groups like SHARE (founded 1955) existed to exchange software. It was common for mainframe hardware to come bundled with software source code. Academics and researchers regularly worked together on code.

But as the software industry grew in the 1970s and early 80s, more and more companies began treating their source code as proprietary secrets. Licenses restricted the ability to modify and redistribute purchased software. This trend deeply concerned Richard Stallman, a programmer at MIT‘s Artificial Intelligence Laboratory. Stallman believed strongly that people should have the freedom to understand, customize and share the software they used.

In 1983, Stallman launched the GNU Project with the ambitious goal of creating an entirely free and open operating system. All GNU code was distributed under the GNU General Public License (GPL), which Stallman drafted to ensure the code would remain free for all to use. The GPL was a groundbreaking new type of software license and remains widely used today.

In 1985, Stallman published the GNU Manifesto laying out his vision, and founded the non-profit Free Software Foundation (FSF) to support the cause. Stallman articulated four essential freedoms defining free software:

0. The freedom to run the program as you wish, for any purpose
1. The freedom to study how the program works, and change it
2. The freedom to redistribute copies so you can help others
3. The freedom to distribute copies of your modified versions to others

For Stallman, "free software" was a moral and ethical imperative – a matter of liberty and social responsibility. As programs grew more complex and integral to daily life, he believed people needed to be in full control of that software, or else risk losing control of their lives. While some dismissed Stallman‘s stance as extreme, his voice gave the movement an ideological foundation to build on.

The Linux Turning Point

By the early 1990s, the GNU Project had created many essential OS components and tools like the GNU Compiler Collection (GCC) and the GNU Debugger. However, its kernel (called Hurd) was incomplete. The kernel is the core that manages the hardware, memory and processes of an operating system. Without one, Stallman‘s dream of a fully free OS remained out of reach.

Enter Linus Torvalds, a computer science student in Finland. In 1991, Torvalds began developing his own Unix-like kernel called Linux and released the source code online. He invited others to contribute improvements. Like GNU code, Linux was licensed under the GPL. Volunteer programmers from around the world collaborated to refine the kernel.

Linux evolved rapidly, and by combining it with GNU software, it was now possible to run a PC using 100% free software. The Linux kernel went on to become the foundation of an entire family of Linux-based OSes including Debian, Red Hat and Ubuntu. It also proved that the open, collaborative development model could produce world-class software on par with proprietary code. The rise of Linux in the 1990s was a major turning point that paved the way for mainstream acceptance of open source.

Coining "Open Source"

Founders of the Open Source Initiative in 1998. Front row center: Eric Raymond and Bruce Perens.

In 1997, Eric Raymond published an influential essay called The Cathedral and the Bazaar contrasting two models of software development:

• The Cathedral model, where code is developed by an exclusive group behind closed doors, as proprietary software is made
• The Bazaar model, exemplified by Linux, where code is developed over the internet collaboratively for all to see

Raymond argued that "given enough eyeballs, all bugs are shallow" and that the open Bazaar model was technically superior. He convinced Netscape to open source its web browser, which became Mozilla Firefox. This brought unprecedented attention to the power of open development.

However, Raymond and others in the community felt that Stallman‘s term "free software" was holding back the movement‘s acceptance in the business world, due to confusion over the word "free." In 1998, they coined "open source" as a more pragmatic and business-friendly term. Bruce Perens adapted Debian‘s Free Software Guidelines into the Open Source Definition, and they founded the Open Source Initiative (OSI) to promote the new term.

Some, including Stallman, felt "open source" focused too narrowly on the practical benefits of access to code, neglecting the deeper issues of freedom and social good at the heart of "free software." But most developers embraced the term, and "open source" caught on widely as the 1990s came to a close.

The Internet Accelerates Adoption

As the internet and World Wide Web took off in the mid-late 1990s, open source development exploded. Projects that would become household names got their start:

• The Apache HTTP Web Server (1995)
• The Perl programming language (1995)
• MySQL database (1995)
• The PHP programming language (1995)

These and countless other open source building blocks played a crucial role in the growth of the internet. The open standards and decentralized, collaborative spirit of the early Web meshed perfectly with the open source ethos. An entire generation of programmers cut their teeth contributing to open source projects.

The first major open source application, the Apache HTTP Server, quickly became the most popular web server software, overtaking proprietary alternatives. It demonstrated that the open source model could produce not just pieces of an OS, but complete applications that were best-in-class. Apache remains the leading web server today, running 24% of all websites.

In the early 2000s, Wikipedia (launched 2001) showed that open source principles could be applied beyond software to create the world‘s largest and most up-to-date encyclopedia. Platforms like SourceForge (1999) and later GitHub (2008) made it much easier to host and manage open source projects. They became thriving hubs for the growing community.

Enterprises Embrace Open Source

Growth in number of repositories hosted on GitHub. Source: Statista

As the open source ecosystem matured, its value proposition became increasingly attractive to companies and organizations:

• Cost: Open source software is generally free, an obvious benefit. Even where support or services are paid, total cost of ownership is often lower.
• Quality and reliability: Community-vetted open source code can achieve excellent quality. Many consider open development more secure and transparent. Large projects are rigorously tested.
• Flexibility and control: Companies can easily customize open source software to their needs. They are not locked into a vendor and have full control of their systems.
• Freedom from vendor lock-in: Open standards and open APIs prevent getting trapped in proprietary platforms. You can always modify the source code.
• Access to innovation: Some of the most cutting-edge development occurs in the open source world as communities share knowledge. It‘s easy to leverage and build on.

In the mid-2000s, seeing these advantages, enterprises began rapidly adopting open source software in earnest. A 2008 Gartner survey found 85% of enterprises were using open source. In 2015, 78% of companies said they run on open source. By 2019, 99% of codebases contained open source components. Even Microsoft, long hostile to the movement, came to embrace open source in the 2010s.

New business models emerged for commercializing open source. Red Hat pioneered selling support and services for open source software. MySQL, Cloudera and others followed an "open core" model, offering a free open source version with paid proprietary add-ons. Cloud providers like AWS began offering managed services based on open source projects. Tension remains between some open source advocates and for-profit business interests. But clearly, open source has proven its economic viability.

Challenges Remain

For all its success, the open source movement still faces significant challenges. Ensuring the sustainability and secure maintenance of widely used open source projects is an ongoing concern. Most open source contributors are unpaid volunteers. Crucial but unsexy work like documentation, testing and bug fixing is often neglected. The open source community has experimented with new funding models like Open Collective, but long-term maintenance remains an unsolved problem.

The decentralized nature of open source has downsides. Lack of clear ‘ownership‘ can make it difficult to quickly address issues like the Heartbleed security bug. The ease of creating new open source projects also means many are abandoned over time, leaving behind security vulnerabilities or broken dependencies for users.

As more and more open source code makes its way into commercial products, compliance with open source licenses can be challenging, leading to costly lawsuits. Initiatives like the OpenChain Project aim to help organizations properly manage their open source dependencies.

Transforming the World

Looking to the future, open source will no doubt continue to play a central role in powering innovation across domains. Virtually all of the big trends in tech – cloud computing, AI/machine learning, Big Data, blockchain, IoT – are driven by open source technologies. As the open source ecosystem grows and matures, supporting its resilience and sustainability will be a key challenge for the global community.

The impact of open source extends far beyond the technology industry. The collaborative development model has inspired approaches to problem-solving in science, government, education and more. For example, open access publishing brings the open source approach to academic research. Governments worldwide are embracing open source software to increase transparency and better serve citizens.

At its core, the open source movement is about more than specific tools and practices. It‘s a radically different and deeply empowering way of creating. One that empowers individuals around the globe to collectively build solutions to shared problems. In a world facing many grave challenges, the open source model offers hope that distributed collaboration can help build a better future.

You can find the full source code for this article, including all images and visualizations, in the GitHub repository here. Comments and pull requests are welcome!