Law is a set of rules established by social or governmental institutions to regulate behavior. It is generally considered to be both a science and an art, though precise definitions vary. In general, laws are statements that describe how things are or should be, such as the law of gravity or the law of supply and demand in economics. The term also may refer to a set of instructions or a code of conduct.

A legal system is the framework that a country’s judges, courts, and lawyers use to interpret the law and resolve disputes. While laws vary widely from country to country, most systems have some similarities based on historically accepted justice ideals. For example, most legal systems include:

a judicial body (court) – a group of judges or barristers that hear and decide cases in the courts of law. Often, court decisions are binding and must be followed by other courts unless the judge can show that it was wrongly decided. The judge must apply the law equally to all parties in a case and must not show favoritism or prejudice.

an arraignment – a court hearing in which the defendant is informed of the charges against him or her, asked to plead guilty or not guilty, and told that if found guilty, he or she will be punished according to the law. The right to a fair trial is guaranteed by the constitutions or laws of most countries.

the doctrine of precedent – the principle that a decision made in an earlier case with similar facts should govern the outcome of a similar current case. This principle is often referred to as stare decisis. It is an important part of common law systems, but not as important in civil law systems where legislation and regulations are more detailed.

a statute – a legislative act that sets out the law as it applies to a specific situation or subject matter. There are statutes for civil, criminal, and administrative law, as well as other areas such as maritime law and bankruptcy.

A code of conduct – a set of principles for a particular profession or area of life that is recognized and enforced by the relevant legal system. For example, there are codes of conduct for doctors, lawyers, and other professionals.

legal philosophy – the principles of justice and fairness that form the basis of law. For example, Blackstone believed that judges should be “the depositories of the law; the living oracles, whose decisions are bound by an oath to decide every doubtful case according to the rules of reason.”

The rule of law – a political and constitutional arrangement in which all citizens and entities are accountable to the law, including those with the most power. This principle requires adherence to the following principles: supremacy of the law, equality before the law, separation of powers, independence of the judiciary, participation in decision-making, transparency, and legal certainty. It is the best way to ensure that a government does not become corrupt or authoritarian.