copyleft

(noun)

The philosophy of using copyrights to enforce freedom of information, especially software source code.

Related Terms

Examples of copyleft in the following topics:

  • Further Resources

    • They offer licenses not just for software, but for text, art, and music as well, all accessible via a user-friendly license selector; some of the licenses are copylefts, some are non-copyleft but still free, others are simply traditional copyrights but with some restrictions relaxed.

  • Complex and Synthetic Media

    • Luria Broth as shown here is made with yeast extract, as yeast extract is not completely chemically defined Luria Broth is therefore an undefined media.By Lilly_M [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0-2.5-2.0-1.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

  • Using Creative Commons Licenses

    • This license is often compared to "copyleft" free and open source software licenses.

  • Openly Licensed Content

    • The Free Art License (FAL), written in 2000, is a "copyleft" (a play on the word "copyright") license that grants the user the right to freely copy, distribute, and transform a creative work without the author's explicit permission.

  • Terminology

  • Digital Media and Intellectual Property Issues

    • Copyleft and free software activists have criticized the implied analogy of digital property with physical property such as land or cars.

  • Aseptic Technique, Dilution, Streaking, and Spread Plates

    • The diluted bacteria were then spread plated.By Leberechtc (Own work) [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-3.0 (http://creativecommons.org/licenses/by/3.0)], via Wikimedia Commons

  • The Rise of Proprietary Software and Free Software

    • If it were in the public domain, any particular copy of it could be incorporated into a proprietary program (as also sometimes happens to code under permissive open source copyright licenses (See the section called "Terminology" for more about "permissive" licensing versus GPL-style "copyleft" licensing.
    • The opensource.org FAQ is also a good resource on this—seeopensource.org/faq#copyleft. ) While such incorporation wouldn't in any way diminish the original code's continued availability, it would have meant that Stallman's efforts could benefit the enemy—proprietary software.The GPL can be thought of as a form of protectionism for free software, because it prevents non-free software from taking full advantage of GPLed code.