Law is a set of rules that are created and enforced by social or governmental institutions to regulate behavior and uphold standards, maintain order, resolve disputes, and protect people’s liberties and rights. Its precise definition is a matter of ongoing debate, with the study of law covering a broad array of issues that range from political philosophy to jurisprudence and criminal justice.

The basic idea behind law is that it should be a relatively stable set of norms available as public knowledge, so that individuals can study it, internalize its principles and expectations, and use it as a framework for planning their lives and settling differences with others. This idea of a rule of law involves procedural requirements like the independence of judges, transparency of government business, and adherence to established legal procedures.

It also assumes that laws should be based on sound reasoning, although the life of law has been more than logic: it has been shaped by the felt necessities of time and place, prevalent moral and political theories, and avowed or unconscious prejudices of judges. Moreover, it has been the product of many different societies at various points in history, each bringing its own particular problems and possibilities to the lawmaking process.

Thus, a major theme in the study of law is how those various societal contexts have influenced the rules that are ultimately enacted. In some countries, such as the United States, a large part of the law is based on the decisions made by judges in resolving cases that have come before them, a body known as case law. In other countries, such as Japan, most of the law is based on statutes, or predetermined sets of rules that govern certain types of situations.

Another important feature of a law is that it should be fairly easy for people to understand and apply: it should provide clear guidelines about what is or is not allowed, so that citizens can plan their affairs and make trades with one another. Similarly, it should be easy for police officers to identify suspects and prosecute them when they break the law.

This is a challenging goal to achieve, particularly given that the cultural and historical contexts in which law is produced vary widely from nation to nation. Each one of these different environments has its own particular problems and opportunities, and the way in which laws are formulated and applied in each context will have a significant impact on how well they serve their principal functions: establishing standards, maintaining order, resolving disputes, and protecting people’s rights. As such, the study of law requires a variety of analytical tools that extend far beyond simple logical analysis.