Private vs. public
An educated citizen should have a clear idea of what the role of government is, and what the role of the market is. New economists base this on fundamental characteristics of the resources and goods which are useful to us.
A private good is a good that can function in the free market. The more a good or service fits in this model, the more efficiently the free market will handle this good. Some qualities of private goods are that they can be made privatized. Think of any consumer good, a piece of food, a toy a car; Our governing system has been able to assign private property on these goods.
Another feature of a private good is that it is rival. Pizza is rival. If i eat the whole pie, there is no slice for you. Information is not. I may have knowledge, and you may have that same knowledge and in almost all cases, information is actually strengthened through sharing.
If a good is niether rival nor excludable it is necessarily a pure public good. If a good can be privatized and is rival it fits perfectly into the free market. When we attempt to privatize public goods we see inefficiency and when we attempt to over-govern private goods we also see inefficiency.