What is open source?

Open source is a term that originally referred to open source software (OSS). Open source software is code that is designed to be publicly accessible—anyone can see, modify, and distribute the code as they see fit.

Open source software is developed in a decentralized and collaborative way, relying on peer review and community production. Open source software is often cheaper, more flexible, and has more longevity than its proprietary peers because it is developed by communities rather than a single author or company.

Open source has become a movement and a way of working that reaches beyond software production. The open source movement uses the values and decentralized production model of open source software to find new ways to solve problems in their communities and industries.

In the 1950s and 1960s researchers developing early internet technologies and telecommunication network protocols relied on an open and collaborative research environment. The Advanced Research Projects Agency Network (ARPANET), which would later become the foundation for the modern internet, encouraged peer review and an open feedback process. User groups shared and built upon one another’s source code. Forums helped facilitate conversation and develop standards for open communication and collaboration. By the time of the birth of the internet in the early 1990s, the values of collaboration, peer review, communication, and openness were written into its foundations.

An open source development model is the process used by an open source community project to develop open source software. The software is then released under an open source license, so anyone can view or modify the source code. 

Many open source projects are hosted on GitHub, where you can access repositories or get involved in community projects. Linux®, Ansible, and Kubernetes are examples of popular open source projects. 

At Red Hat, we use an open source software development model to create our enterprise open source products and solutions. Red Hat developers actively participate in hundreds of open source projects across the IT stack.

We start with community-built open source software that meets the needs, partially or fully, of our customers. Red Hat builds upon these open source projects, hardening security, patching vulnerabilities, and adding new enterprise features.

We then contribute these improvements back to the original project for the benefit of the community as a whole.

As customers use our software, they provide feedback, submit bug reports, and request additional features as their needs shift. This input guides Red Hat's development.

Linux is a free, open source operating system (OS), released under the GNU General Public License (GPL). It’s also become the largest open source software project in the world.

The Linux operating system was created as an alternative, free, open source version of the MINIX operating system, which was itself based on the principles and design of Unix.

Because Linux is released under an open source license, which prevents restrictions on the use of the software, anyone can run, study, modify, and redistribute the source code, or even sell copies of their modified code, as long as they do so under the same license.

For a long time open source software held the earlier label of "free software." The free software movement was formally established by Richard Stallman in 1983 through the GNU Project. The free software movement organized itself around the idea of user freedoms: freedom to see the source code, to modify it, to redistribute it—to make it available and to work for the user in whatever way the user needed it to work.

Free software exists as a counterpart to proprietary or "closed source" software. Closed source software is highly guarded. Only the owners of the source code have the legal right to access that code. Closed source code cannot be legally altered or copied, and the user pays only to use the software as it is intended—they cannot modify it for new uses nor share it with their communities.

The name "free software," however, has caused a lot of confusion. Free software does not necessarily mean free to own, just free to use how you might want to use it. "Free as in freedom, not as in beer" the community has tried to explain. Christine Peterson, who coined the term "open source," tried to address this problem by replacing ‘free software’ with ‘open source’: "The problem with the main earlier label, ‘free software,’ was not its political connotations, but that—to newcomers—its seeming focus on price is distracting. A term was needed that focuses on the key issue of source code and that does not immediately confuse those new to the concept."

Peterson proposed the idea of replacing "free software" with the term "open source" to a working group that was dedicated, in part, to shepherding open source software practices into the broader marketplace. This group wanted the world to know that software was better when it was shared—when it was collaborative, open, and modifiable. That it could be put to new and better uses, was more flexible, cheaper, and could have better longevity without vendor lock-in.

Eric Raymond was one of the members of this working group, and in 1997 he published some of these same arguments in his wildly influential essay "The Cathedral and the Bazaar". In 1998, partly in response to that essay, Netscape Communications Corporation open sourced their Mozilla project, releasing the source code as free software. In its open source form, that code later became the foundation for Mozilla Firefox and Thunderbird.

Netscape’s endorsement of open source software placed added pressure on the community to think about how to emphasize the practical business aspects of the free software movement. And so, the split between open source and free software was cemented: "open source" would serve as the term championing the methodological, production, and business aspects of free software. "Free software" would remain as a label for the conversations that emphasized the philosophical aspects of these same issues as they were anchored in the concept of user freedoms.

By early 1998 the Open Source Initiative (OSI) was founded, formalizing the term open source and establishing a common, industry-wide definition. Though the open source movement was still met with wariness and corporate suspicion from the late 1990s into the early 2000s, it has steadily moved from the margins of software production to become the industry standard that it is today.

There are lots of reasons why people choose open source over proprietary software, but the most common ones are:

• Peer review: Because the source code is freely accessible and the open source community is very active, open source code is actively checked and improved upon by peer programmers. Think of it as living code, rather than code that is closed and becomes stagnant.
• Transparency: Need to know exactly what kinds of data are moving where, or what kinds of changes have happened in the code? Open source allows you to check and track that for yourself, without having to rely on vendor promises.
• Reliability: Proprietary code relies on the single author or company controlling that code to keep it updated, patched, and working. Open source code outlives its original authors because it is constantly updated through active open source communities. Open standards and peer review ensure that open source code is tested appropriately and often.
• Flexibility: Because of its emphasis on modification, you can use open source code to address problems that are unique to your business or community. You aren’t locked in to using the code in any one specific way, and you can rely on community help and peer review when you implement new solutions.
• Lower cost: With open source the code itself is free—what you pay for when you use a company like Red Hat is support, security hardening, and help managing interoperability.
• No vendor lock-in: Freedom for the user means that you can take your open source code anywhere, and use it for anything, at anytime.
• Open collaboration: The existence of active open source communities means that you can find help, resources, and perspectives that reach beyond one interest group or one company.

Open source is about a lot more than code. At Red Hat, we celebrate what communities are doing with open source technology today with Open Source Stories. Open Source Stories is a multimedia series that celebrates how community, meritocracy, and a free exchange of ideas can unlock potential across a range of disciplines. Check out these recent highlights:

• What are the farmers of tomorrow doing with open tools and principles today?
• Learn how a teacher and an afterschool club built a creative community through open leadership and transformed a school and a city in the process.
• Femi Owolade-Coombes discusses how the power of open source and community can unlock potential for young coders.
• Alicia Gibb explains what the open hardware movement is and why it matters.

Red Hat is the largest open source company in the world. We build and support open source products from open source projects. We give back to the projects and communities we engage in. We defend open source licenses. With open source, we equip our customers for success. We take community-built code and harden its security, add features, and make it enterprise-ready and scalable. Then we push these improvements back out to the original project to benefit the community as a whole.