How would you define a law?

How would you define a law? How does the creation of laws affect society? How can the creation of laws at local, state, and federal levels be improved? What role have courts played in the history of the United States? How has the organization of U.S. courts evolved over time?

Not looking for long answers or anything. I will be grateful if anyone could just at least answer my question with short answers.

Laws are the rules a society lives by. They allow us to do the things together that we can do more efficiently than we could do as individuals and are supposed to keep the playing field level between us.

In my view, the best improvement would be a constitutional amendment that prevents candidates for public office from accepting donations from any person or organization not qualified to vote in that election. That would insure that our elected officials owe their allegiance to the people who elected them, not to the people who paid for their campaign.

The courts interpret the laws and apply them to cases brought before them. Those interpretations become precedents that are applied to future cases. In effect, that makes their decisions part of the law as it is applied. Through history, many of the most critical changes in our Constitution and our laws have been made by the court system, not the legislators.