Week 1 Lesson 2v3: Open Source Software: Definition and Rights

Open Source Definition and Its Rights
  • The Open Source Initiative (OSI) defines open source software through 10 rights, which encapsulate the four freedoms but are tailored for business concerns.
The Ten Rights of Open Source Software

  1. Freedom of Redistribution

    • Users have the right to redistribute copies of the original source code, allowing for widespread sharing.

  2. Access to Source Code

    • The source code must be accessible; this is fundamental to the term "open source."

  3. Derivative Works

    • Users can create derivative works based on the original source code, ensuring flexibility in modification.

  4. Integrity of the Author's Source Code

    • If modifications are made, the modified version must be named differently to prevent confusion about authorship, especially in cases where altered code represents views contrary to the original author.

  5. No Discrimination

    • There should be no discrimination against individuals or groups, meaning any person can use the software regardless of their identity.

  6. No Discrimination Against Fields of Endeavor

    • The software cannot be restricted from use in certain fields (e.g., military, charity).

  7. Distribution of the License

    • A written license must be provided with the software, explaining user rights clearly.

  8. License Must Not Be Product-Specific

    • The license should not limit usage to a specific hardware product (e.g., only laptops).

  9. License Must Not Restrict Other Software

    • Users should be able to run the software alongside any other software; there should be no restrictions.

  10. Technology Neutrality

    • The license should not restrict the operating system or equipment on which the software can run.
Challenges with Licensing
  • The OSI's acceptance of nearly 100 different licenses complicates understanding and compliance due to variations and incompatibilities, leading to confusion in the community.
  • GitHub provides resources, including a series of videos, to help individuals navigate licensing issues.
Popular Open Source Licenses

  • MIT License

    • Formed in the 1980s to allow researchers to retain trade secrets while sharing their software. Offers broad rights without requiring changes to be shared back.

  • Apache License

    • Allows developers to use, modify, and distribute code without needing to contribute modifications back to the original source. Users can create distinctly named versions without restrictions.

  • BSD License (3-clause and 2-clause)

    • Requires credit to the original author but allows great freedom in how the software is used and modified.

  • ISC License

    • A simplified, permissive license used for core technologies on the internet, similar to MIT and Apache.

  • Mozilla Public License (MPL)

    • Allows mixing proprietary technology with open source, providing flexibility for development while maintaining protections for proprietary components.
Comparison: Free Software vs. Open Source Software

  • Free Software (from the Free Software Foundation):

    • Focuses on user freedoms and moral considerations rather than price. Users are entitled to four essential freedoms as articulated by Richard Stallman.

  • Open Source Software (defined by OSI):

    • Centered on practicality and enterprise appeal, using the four freedoms as a foundation but prioritizing superior design methodologies over moral issues.
Conclusion
  • The OSI's definition of open source led to significant developments linking software licenses and enterprise solutions, paving the way for open source software's evolution and its impact on businesses.