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The license VDR Wiki uses grants free access to our content in the same sense as free software is licensed freely. This principle is known as copyleft. That is to say, VDR Wiki content can be copied, modified, and redistributed so long as the new version grants the same freedoms to others and acknowledges the authors of the Wikipedia article used (a direct link back to the article satisfies our author credit requirement). VDR Wiki articles therefore will remain free forever and can be used by anybody subject to certain restrictions, most of which serve to ensure that freedom.
To fulfill the above goals, the text contained in VDR Wiki is licensed to the public under the GNU Free Documentation License (GFDL). The full text of this license is at Text of the GNU Free Documentation License.
The text of the GFDL is the only legally binding document.