in old English law, was a tract of ground shared by residents of a village, but owned by no one. A common, or commons, could be grazing grounds, or the village square, but it was property held in common for the benefit of all.
More recently, a wide variety of resources have become identified as commons. These include the Internet, health care, urban space, the atmosphere, the open sea and Antarctica, etc. That usage expands the meaning to include those new kinds of shared resources and innovations that meet certain criteria. Such criteria are not absolute, but represent a continuum between opposite poles. Certain commons may meet some of the criteria, and not others. A new commons is a resource that meets a preponderance of the following criteria, with the criterion at the left of the arrow being more commons-like, and those to the right being less indicative of commons:
Resource is recognized as a commons ↔ Resource is not recognized as a commons
Users with a stake in the resource are identifiable ↔ No stakeholders are identified or identifiable
Users recognize their interdependence ↔ Users think of their use as independent.
Conflicts between individual and group interests:
Conflicts prevail between individual and group interests (i.e., social dilemmas related to the commons) ↔ No conflicts between individual and group interests
It is vulnerable to failure (e.g., depletion, degradation, privatization, etc.) in the future ↔ The resource is stable and not threatened.
The resource requires participatory management ↔ The resource is self-sustaining.
Appropriate rules are necessary to govern the resource ↔ Rules are not needed.
The rules are created from within ↔ The rules are created by outsiders or from top down.
 Charlotte Hess, Howard Rheingold, Andrea Saveri, Kathi Vian, Kathryn Milun, Marc Smith, Josh Teneberg, and Matt Chwierut, resulting from a workshop Institute for the Future (IFTF), Palo Alto CA, 19 April 2007, and refined via wiki discussion. It builds on the work of Hess, Charlotte. “Is There Anything New Under the Sun? A Discussion and Survey of Studies on New Commons and the Internet,” presentation at “Constituting the Commons: Crafting Sustainable Commons in the New Millennium,” the Eighth Conference of the International Association for the Study of Common Property, Bloomington, Indiana, 31 May–4 June 2000, at: http://dlc.dlib.indiana.edu/archive/00000512/.