Concepts / Open source software
Source code is the code humans write (although perhaps with the help of software) before it’s converted into the code a computing device runs. Open source software (OSS) means that the source code is freely licensed for anyone to use and change without permission or charge. It is a form of open design.
Just as open protocols may be subsumed by platform dominance, it’s worth noting that OSS plays a part in a complex system, the outcomes of which may seem at odds with the intention.
Take the Android operating system for example. Google publishes the source code under an OSS license, but the license does not grant rights to the Android trademark nor to a bundle of Google-operated services that many consider to be essential to the operating system user experience. The operating system may be OSS but Google has centralized power over the Android ecosystem.