Examples
When you consume education you get a private benefit. But there are also benefits to the rest of society. E.g you are able to educate other people and therefore they benefit as a result of your education. (positive consumption externality)
A farmer who grows apple trees provides a benefit to a beekeeper. The beekeeper gets a good source of nectar to help make more honey. (positive production externality)
If you walk to work, it will reduce congestion and pollution; this will benefit everyone else in the city.
