open source
Software whose source code is publicly available for anyone to view, use, modify, and distribute, typically under a specified licence.
Full Definition
Open source refers to software released under a licence (such as MIT, Apache 2.0, or GPL) that grants users the rights to inspect, modify, and redistribute the source code. In editorial contexts, the term is a noun phrase ('this project is open source') and a compound modifier before a noun ('an open-source library'). A common style error is hyphenating the noun form or failing to hyphenate the adjectival form. Editors should also be aware of related terms: 'open-source software' (OSS), 'free software' (a related but distinct concept), and 'source-available' (code visible but with restrictions).
Usage
Usage note: Hyphenate as a compound modifier ('open-source tool') but not as a predicate ('the tool is open source'). Do not treat 'open source' and 'free software' as synonyms; they reflect different philosophical frameworks.
In Context
- "The project is open source and accepts contributions from the community under the Apache 2.0 licence." — Project README
- "Evaluate three open-source linting tools before recommending one for the CI pipeline." — Engineering evaluation report