The WHOLE EARTH CATALOG functions as an evaluation and access device. With it, the user should know better what is worth getting and where and how to do the getting.
An item is listed in the CATALOG if it is deemed:
1) Useful as a tool,This information is continually revised according to the experience and suggestions of CATALOG users and staff.
2) Relevant to independent education,
3) High quality or low cost,
4) Not already common knowledge,
5) Easily available by mail.