License For Textbooks — GNU FDL Or CC?

An anonymous reader writes 'I'm a college professor who is putting together an open-source textbook. I'm trying to decide between using the GNU Free Documentation License or the Creative Commons Attribution 3.0 United States License. I don't really understand the difference between these, though it seems with the Free Documentation License I need to include a copy of the license in my text. Which do you advise using?'

understanding the GPL

[mosel-saar-ruwer]

I don't really understand the difference between these

The GPL is an utterly unintelligible document.

Stallman and the English language are completely strangers to one another.

Re:

[mlinksva]

I find the GPL readable. In any case, this post doesn't ask about the GPL. It asks about the GFDL.

do you want copyleft or not?

[mlinksva]

The GFDL and CC-BY are rather different licenses. The first is a copyleft license (requires adaptations to be distributed under the same license), the latter is a permissive license (do anything you want so long as you give credit, roughly).

If you don't want copyleft, CC-BY is your choice.

If you do want copyleft, it would make sense to choose between GFDL and CC-BY-SA, which you can think of as the copyleft version of CC-BY. Wikipedia (and other Wikimedia sites) migrated from the GFDL to CC-BY-SA as their primary content license in June, see http://creativecommons.org/weblog/entry/15411 [creativecommons.org]

Thanks for not considering a more restrictive license. :)

my experience

[bcrowell]

I'm also a college professor, and I've done the same thing [lightandmatter.com] you're doing. I originally used GFDL, because CC didn't exist yet. Later I switched to a dual-licensing scheme with both GFDL and CC-BY-SA, because I wanted to be able to share with other people using CC-BY-SA. Eventually Wikipedia switched all of its licensing from GFDL to CC-BY-SA, so I've dropped the GFDL licensing. So rather than the two options you mentioned, let me discuss three:

1. CC-BY-SA - You can use other people's materials that are CC-BY-SA licensed. This includes Wikipedia, for photos. The Share-Alike (SA) part means that other people can only use your work if the thing they're using it in is under the same license; this eliminates the feeling that someone will cynically exploit your work for their own commercial gain, in a project that they themselves will not make freely available.
2. GFDL - You can use other people's materials that are GFDL licensed, but this isn't such a big benefit, since there isn't that much GFDL content out there anymore. (WP used to be GFDL, but essentially everything on there is now relicensed under CC-BY-SA.) You get the same Share-Alike thing as with CC-BY-SA.
3. CC-BY - This is a very liberal license. It says anyone can use your work, even in a commercial product that is not free.

My recommendation would be CC-BY-SA. Another possibility would be dual-licensing with CC-BY-SA and GFDL, but that's probably not worth the extra work unless you've identified materials you want to use that are under GFDL. Only do CC-BY if you simply want to make a gift to the world, and you don't care if your work is repackaged into something non-free by other people.

Re:

[bcrowell]

Oops, sorry for the reply-to-self, but I thought of something else I wanted to mention. GFDL says that if other people use your work to make their own derived works, they have to provide the derived work in at least one editable format, such as an OpenOffice or LaTeX file. That makes it kind of silly to put out your book under GFDL unless you can and will release it in at least one format that's editable with open-source software; you can do it, but it makes it difficult or impossible for other people to us

Re:

[mlinksva]

Great summary. Two tiny things:

Another possibility would be dual-licensing with CC-BY-SA and GFDL, but that's probably not worth the extra work unless you've identified materials you want to use that are under GFDL.

If the things they want to use are GFDL-only and the product is an adaptation of those then they don't have the option of dual licensing. You may have meant "you want your work to be incorporated into that are under GFDL."

Only do CC-BY if you simply want to make a gift to the world, and you don'

Re:

[bcrowell]

>>Another possibility would be dual-licensing with CC-BY-SA and GFDL, but that's probably not worth the extra work unless you've identified materials you want to use that are under GFDL.

>If the things they want to use are GFDL-only and the product is an adaptation of those then they don't have the option of dual licensing. You may have meant "you want your work to be incorporated into that are under GFDL."

I don't think this is correct. This issue came up for me, and initially I thought the same

Reverse passing-off

[tepples]

CC-BY isn't quite a pure gift -- it could be used by a selfish licensor if that person only cares about maximizing the amount of credit they get -- incorporating CC-BY works into non-free works still requires giving credit.

In some contexts, even use of a public domain work (CC Zero or sufficiently old works) requires credit lest an author be accused of plagiarism or reverse passing-off. When registering a copyright with the U.S. Copyright Office, for instance, you have to disclose the PD works incorporated into your own work. Ashton-Tate v. Fox.