7. Impact of copyleft on license choice
Copyright and copyleft Copyright exist to protect authors of intellectual property from unauthorized copying and/or selling of their work. Copyleft makes it possible to modify and distribute software or documentation to the community, but only on the condition that modified software remains Libre*. *This means that the product is free and cannot be commercialized. There are several types of copyleft licenses that vary in strength. We will give an example of Strong, Medium, Weak and Free license. • One of the strongest licenses is GNU APGL . The product can be redistributed for free, it can be used an unlimited number of times, the product must be open source, and this license must be extended to all derivative modifications of the product. This license is used by programs such as MediaGoblin and CKAN • When it comes to licenses of "medium" strength, the license first comes to mind is GNU GPL . This license is very similar to the GNU AGPL, but if the program ...