Open source license

An umbrella term for software that is licensed with some combination of characteristics. The universal feature of open source software is that the source code is available for anyone to inspect. Other common, but non-universal, characteristics include the ability to download the source code and run it for free, the ability to modify the code and redistribute it, and the distributed ownership of the software among a large set of contributors and editors.

Source: Open Source Voting in San Francisco, City and County of San Francisco