In economics, a public good (also referred to as a social good or collective good)[1] is a good that is both non-excludable and non-rivalrous. Use by one person neither prevents access by other people, nor does it reduce availability to others.[1] Therefore, the good can be used simultaneously by more than one person.[2] This is in contrast to a Common Good, such as wild fish stocks in the ocean, which is non-excludable but rivalrous to a certain degree.
https://en.m.wikipedia.org/wiki/Public_good_(economics)
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