Common resources are those that no one individual or organization can lay claim to. These may include public spaces (such as parks or nature preserves), certain natural resources (such as fish in the sea), and so on.
A common resource (or the "commons") is any scarce resource, such as water or pasture, that provides users with tangible benefits but which nobody in particular owns or has exclusive claim to. A major concern with common resources is overuse, especially when there are poor social-management systems in place to protect the core resource.
