Law is the system of rules a society recognizes and enforces to regulate its members’ activities. It is a broad subject area that encompasses a variety of fields, including criminal law, family law, international law and tax law. In addition, laws shape politics, economics and history in diverse ways. Among its many functions, laws serve to keep the peace, preserve the status quo, ensure equal opportunity and promote social justice. Different legal systems achieve these goals more or less effectively. For example, an authoritarian government might keep the peace and maintain the status quo but may oppress minorities or political opponents (e.g., Burma or Zimbabwe).
A key component of law is judicial precedent—the use of previous court decisions to guide future cases with similar issues. Judges rely on case law when deciding how to interpret statutes and other legal codes. In the United States, for instance, the Supreme Court and other appellate courts use the decisions of lower courts that can review their decisions in interpreting federal law.
Other areas of law include tort law, which provides compensation for damages caused by negligence or wrongdoing (auto accidents and defamation are examples). Property law defines people’s rights and duties toward tangible things such as land and buildings, and intangible goods like books and stocks.
Law also covers regulatory law, which sets standards that private companies must meet when providing public services and utilities such as water or energy. In a broader sense, it includes the field of international law, which addresses human activities in outer space and other global issues via treaties and other agreements.