In general the difference between these two is that public laws involve relations between the individual and the state whereas private laws involve the relations between individuals. As an example of this, the law of wills is a matter of private law. The state does not have a stake in who inherits when someone dies. However, there are clearly individual people who are affected by the rules of inheritance. By contrast, there are areas of law like theft. When I steal from another person, I do hurt them, but I also hurt society as a whole because I make everyone feel less secure. In this way, public laws have to do with issues that affect society as a whole while private law is more about issues that matter only to the individuals involved.