Update: There seems to be something on the move with GFDL / Creative Commons for Wikipedia contents. Look here to see what Jimbo Wales said: http://blog.jamendo.com/index.php/2007/12/01/breaking-news-wikipedia-switches-to-creative-commons/

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just a few things...

Why not just use the Creative Commons?

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Creative Commons did not exist when Wikipedia was created in early 2001. The Attributions-ShareAlike license is very similar in spirit to the GFDL, but not quite compatible with the present GFDL.

Why not switch to license XYZ?

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Even if we wanted to, that's not really possible.
Because contributors retain copyright to their submissions, it's not possible to unilaterally change the license, unless the Free Software Foundation consents to the change in a new version of the GFDL.
Note, you could try dual licensing your stuff (see Guide to the CC dual-license) but that might not get very far if many other users do not follow suit.

What about invariant sections? Everyone says those are trouble.

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Wikipedia doesn't accept invariant sections. While someone could create a derivative work from Wikipedia material and include invariant sections in that, the original Wikipedia version will remain unencumbered.


I heard there's something about citing five primary authors. What's up with that?

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The GFDL requires that derivative works list the "primary authors" of the original work on the title page, up to 5 if there are more.
There have been some suggestions on how best to make it easy to deal with this requirement by automatically extracting a list of authors from page history, but this isn't fully realized yet.

Title page??

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The GFDL was originally meant for software documentation, such as manuals. For Wikipedia as a whole, the main page(s) can be considered as the title page. For extracting individual articles...?

Other opinions and info on the GFDL

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