Public goods
From ACT Wiki
Economics.
Examples of 'pure' public goods include flood control, street lighting, policing and national defence.
The definition of public goods includes non-rivalry and non-excludability.
Non-rivalry means that when a public good is enjoyed, it doesn’t reduce the amount available for other people.
Non-excludability means that it is not possible both to provide such a good and prevent others enjoying it. For this reason, public goods are more likely to be efficiently provided by the public sector, rather than by the private sector.
