GFDL

The license wa uses grants free access to our content in the same sense as free software is licensed freely. This principle is known as copyleft. All content can be copied, modified, and redistributed so long as the new version grants the same freedoms to others and acknowledges the authors. 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 here is licensed to the public under the GNU Free Documentation License (GFDL).

• Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts.