Externalities
An externality occurs when the production or consumption of a good or service creates external costs and/or external benefits. These side effects are known as externalities.
Private Costs
These refer to the cost of the user of the product/service
Social costs
These refer to the cost to society as a whole due to the product or service.
Private benefits
These refer to the benefits to the individual of the good or service
Social benefits
These refer to the benefits to society as a whole of the good or service.