Today, open source spans every continent and underpins most of the world’s online infrastructure. What began as a small academic and hobbyist practice grew into a global model for building software collaboratively.
When sharing code was the default
In the 1960s and early 1970s, computers were large, expensive, and usually tied to universities or research labs. Programmers often worked in small groups, exchanged source code informally, and learned by modifying each other’s software. Code circulated through printed listings, tapes, and local networks, reaching only a few institutions.
At this stage, the idea of restricting source code access was not yet common. The priority was to solve problems and improve the software through collective effort. This culture shaped the first generation of developers, who later defined open collaboration principles.
The UNIX influence
A major catalyst arrived with the development of UNIX at Bell Labs. The system was elegant, modular, and built to encourage experimentation. Universities licensed it at low cost, which allowed a global academic network to study, extend, and adapt it. Students and researchers added tools, rewrote components, and formed communities around new features.
This distributed development model introduced the idea that complex systems could evolve through many small, independent contributions. That model still defines open-source workflows today.
The four freedoms
By the early 1980s, commercial software firms began restricting access to source code. Richard Stallman, an American free software movement activist and programmer, responded by launching the GNU Project and the Free Software Foundation. He introduced the four freedoms: the right to run, study, modify, and distribute software.
This was a turning point. It reframed software from a tool to something that users should control. The GNU General Public Licence enforced these freedoms legally, creating the first widely used copyleft licence. Many of today’s open-source projects still rely on it.
The rise of permissive licensing
Alongside GNU, another strand of the movement developed through permissive licences such as BSD and MIT. These licences placed minimal restrictions on reuse and were rooted in the academic culture of open research. They encouraged industry adoption and helped open source spread through commercial environments.
The coexistence of copyleft and permissive approaches gave developers flexibility. That diversity remains a strength of the open-source ecosystem.
Early communication channels
Long before GitHub existed, open-source communities used mailing lists, Usenet groups, and FTP servers to coordinate projects. These channels supported distributed contributions and peer review. They also helped build a shared identity among developers who had never met in person.
Many foundational projects, including Linux, the Apache HTTP Server, PostgreSQL, and Perl, grew from these networks. Their maintainers relied on open communication, shared ownership, and transparent decision-making, practices that remain central to modern development communities.
The foundations for global growth
By the end of the 1990s, open source had established a clear identity that combined technical collaboration with social principles. The term “open source” itself emerged in 1998 to encourage broader industry acceptance. That shift led large organizations to join and support the movement rather than resist it.
These early foundations allowed open source to grow beyond academic circles into civic technology, humanitarian computing, security research, and global cloud infrastructure. The movement’s strength rests on the same principles that shaped its earliest days: transparency, co-operation, and the ability for anyone to contribute.
Today’s global communities follow patterns established decades ago. They work through shared repositories, open discussion, and peer review. They maintain projects that anyone can adapt and build upon.