Open Source Software

Open-source software is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. Open-source software may be developed in a collaborative public manner.

The open-source model is a decentralized software development model that encourages open collaboration. A main principle of open-source software development is peer production, with products such as source code, blueprints, and documentation freely available to the public.

The open-source movement began as a response to the restrictions of proprietary software. In 1983, Richard Stallman launched the GNU Project to create a free Unix-like operating system, and in 1985 he published the GNU Manifesto, which outlined his motivation for creating free software. The Open Source Initiative was founded in 1998 to promote open-source software.

Today, open-source software powers much of the modern internet and computing infrastructure. The Linux kernel, which is open source, runs the majority of the world's servers, supercomputers, and Android smartphones. The Apache web server, the MySQL database, the Python programming language, and thousands of other critical tools are open source.

Many of the world's largest technology companies — including Google, Microsoft, and Meta — contribute extensively to open-source projects and release their own tools under open-source licenses. They do this because open-source development allows them to benefit from the contributions of thousands of external developers and to build goodwill in the developer community.

Open source has also inspired open models in other fields, including open access academic publishing, open educational resources, and open government data.