Commons
The commons are the cultural and natural resources accessible to all members of a society, including natural materials such as air, water, and a habitable Earth. These resources are held in common even when owned privately or publicly. Commons can also be understood as natural resources that groups of people manage for individual and collective benefit. Characteristically, this involves a variety of informal norms and values employed for a governance mechanism. Commons can also be defined as a social practice of governing a resource not by state or market but by a community of users that self-governs the resource through institutions that it creates.

The Commons Explained in 15 Minutes | David Bollier
New to the Commons? | David Bollier
If you’re coming to the commons for the first time, it can be difficult to grok the idea because there are so many different ways to understand the commons. That’s because the commons is not so much a fixed, universal thing as a general concept describing durable, dynamic sets of social relationships for managing resources -- all sorts of resources: digital, urban, natural, indigenous, rural, cultural, scientific, to use some crude categories.
The Commons, Short and Sweet | David Bollier
I am always trying to figure out how to explain the idea of the commons to newcomers who find it hard to grasp. In preparation for a talk that I gave at the Caux Forum for Human Security, near Montreux, Switzerland, I came up with a fairly short overview, which I have copied below. I think it gets to the nub of things.