"GB" == Guillaume Blanchard gblanchard@arcsy.co.jp writes:
GB> This statement is right? License compatible with GFDL:
That depends on what you mean by "compatible". If you mean, "you can include works under license X with works under the GFDL", practically any value of X will work.
If you mean, "You can re-license a work made under the license X under the GFDL", then X can only be "public domain", "GFDL", or something BSD-like (such as CC-BY).
If you mean "You can re-license a work made under the GFDL under license X", then it's just the GFDL.
If you mean, "You can dual-license a work under both license X and the GFDL," then it can be practically any license. HOWEVER, dual-licensing with copyleft licenses only lasts for one generation: people who make derivative works have to decide which license to choose, and license under only that. No current copyleft license allows you to re-license under a license with a similar spirit but different details.
If it's not clear already, dual licensing is a lot of trouble. The idea is nice, but it makes for a lot of head-scratching.
GB> By the way, no one answer my question about if derivation is GB> allowed with fair use image and who decide the fairness of a GB> picture?
There's a good Web site here with info on fair use:
Fair use (or fair dealing) is not a license. It is an exception to US and Commonwealth country copyright law that says that you can make unauthorized copies or excerpts of work under certain circumstances.
Fair use is a _defense_ if you are sued for copyright violation. The courts decide if your unauthorized copying is excusable under the principle of fair use. In the US, it depends who you are, why you're using the copyrighted work, how much you're using, and what the effect is on the copyright holder and the market. It is a complicated and subjective decision. In other countries, the rules are different.
~ESP