Two-tiered system According to Sanger, the
expert wiki was expected to be written and managed by experts, while the
public wiki was expected to be editable by members of the educated public. Only registered users who had provided their
real names would be permitted to edit the wiki.
Content Around 2000 content pages existed as of August 2007. The Digital Universe claims the following featured portals: Earth, Energy, The Arctic, Texas Environment, U.S. Government, and
Salton Sea. The Earth portal is working on an
Encyclopedia of Earth (EoE), which will focus on the
natural environment and its interaction with society. It will limit editing privileges to experts, by attributing all edits to their authors, by changes being published publicly only after approval and by using an expert-developed taxonomy for articles. The EoE runs
MediaWiki wiki software. EoE is to use the
Creative Commons Attribution-ShareAlike 2.5 for its license. Over 400 articles had been written by experts by January 2006. ==Development==