A public good is a good which has two important characterstics:
(i) Non-Rival : From non-rival, we mean that the consumption level obtained from the public good cannot be reduced if one person consumed it. The same level of satisfaction is available for the next individual which means that the consumption level of public good cannot be reduced with the consumption of the individuals.
(ii) Non-Excludable : From non-Excludable, we mean that one person cannot exclude others from the consumption of public good even if they are not paying for that good.
