Open-source software

Software with publicly available source code

Open-source software (OSS) is computer software whose source code is publicly available, allowing users to use, study, modify, and distribute it — in contrast with proprietary (closed-source) software. These abilities are typically granted through open licenses or, more rarely, by dedication to the public domain. The development of open-source software can be based on open collaboration, a decentralized model of production.

From Wikipedia, under CC BY-SA. More on occurri.