Public good is a term in economics which refers to the good (commodity) that is available for use for everybody and one person’s usage of it does not diminish or exhaust its availability to others. It is considered non-excludable and non-rivalrous. Examples of public goods are education, infrastructure, lighthouses, flood control systems, knowledge, fresh air, national security, official statistics, etc. The public good is different from the common good in that a common good, though non-excludable, tends to be semi-rivalrous in nature. Examples of common goods would be timber, coal, etc. Public goods are useful for the population as a whole.
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