A system of rules that regulates the conduct of people and is enforced by a controlling authority through penalties. Law is a broad term and its precise definition has been the subject of longstanding debate.

The law is a complex set of principles and procedures that govern human relationships, society, business, and the government itself. It encompasses many different areas, from contracts to criminal justice. Many careers involve the study of laws and how they work, including careers as lawyers, judges, and government officials.

Different parts of the world have different legal systems, with some relying on codified statutes while others use case law or a combination of both. The law has evolved over time to reflect social changes and cultural values. For example, slavery was once permitted in most states and the death penalty was used to punish treason, but both of these practices are now prohibited.

A common theme is the desire to have a law that is both fair and understandable. This requires that the public know what laws are being made and why, and that they can participate in the process of making and applying the law. This is sometimes called transparency and rule of law.

In the United States, for instance, a judge presides over cases in which citizens sue their government or other people for wrongdoing. A lawyer for the plaintiff or defendant prepares a brief that explains to the judge how the law should be applied in the case. This information is then included in the court record, which is known as the docket. In addition to judicial officers, other personnel working in a court include probation officers (who screen applicants for pretrial release) and public defenders (who represent defendants who can’t afford attorneys in criminal cases).

When a case goes to trial, the judge gives a series of instructions to the jury about how the law applies to the facts of the case. A court may also refer to previous decisions in deciding how the law should apply to new situations, a practice called binding precedent. These prior decisions are considered important enough to bind all courts that can review them, including federal appeals courts and the Supreme Court of the United States.

The rule of law is the concept that all people and institutions, including the government itself, are accountable to laws that are publicly promulgated, equally enforced and independently adjudicated. It also means that the government is held to high standards of transparency, participation, and accountability. This type of rule is essential to a democracy. In some countries, people have fought for decades to establish this kind of law.