What is open source software?

Open source software means that the human-readable source code is available to the public for others to use, copy, learn from, and modify for their benefits. All kinds of software can be open source, from operating systems and under-the-hood utilities to web browsers and user-facing apps. The majority of the world’s software is open source, and some estimates say that nearly all software has some open source components to it. Chances are high that your organization is already using open source software, either directly or through other software that depends on it.

While open source software (OSS) can, at a bare minimum, simply mean releasing the source code publicly, the underlying principles of open source go further than that. In the case of public sector products, OSS is at the core of reuse. For organizations who wish to create something that others can reuse easily, it is fundamental to adhere to open source principles. Note that “open source is different than “coding in the open.” Coding in the open means publishing the source code of a system or application without taking care to ensure its reusability. Open source aspires to something larger: software that is not only available for reuse, but built and maintained to ensure reusability.

Open source software is released with specific licenses that outline the permitted usage of the source code. Not all open source code can be used in any fashion. When using open source tools, it is important to review the license to ensure you abide by its allowances and restrictions. When opening your own resources, it’s critical to provide a license that makes clear what the resources can be used for. Common licenses are reused across many open source projects, such as the MIT license or the GPL license. By using common licenses, projects reduce the burden of understanding unique license terms and provide clear and well-understood terms to the use of their resources.

Why Use Open Source?

The benefits of using open source principles is well understood and documented by the software community. Anna Shipman, former Open Source Lead with the UK’s Government Digital Service, articulated an excellent set of benefits for open sourcing your own work: