Licensing

/ˈō-pən sȯrs ˈsȯft-ˌwer/

noun — "software whose source code is available to inspect, modify, and share."

Open Source Software is software distributed under a license that allows users to view, study, modify, and redistribute its source code. Unlike proprietary software, where the underlying implementation is typically hidden and controlled by a single vendor, open source software exposes the code itself, enabling anyone to understand how it works and, within the terms of its license, build upon it.