Law consists of the sets of restrictions, policies, statutes and guidelines that people agree to follow in their societies. From a societal viewpoint, the law promotes rationality, fairness, order and morality. From a judicial point of view, the law implies commandments (backed by the threat of penalties) from a sovereign authority to which citizens have a natural obligation of obedience.
Law governs many aspects of people’s lives in all parts of the world. It influences relationships, governance, commerce and human rights. It has a diverse, expanding and evolving nature, underscored by numerous branches of the law: contract law regulates agreements to exchange goods and services; criminal law defines crimes, their punishments and other details governing policing and prosecution; corporate and securities laws define business practices and partnerships; family law establishes marriages, divorces, child custody and other issues involving families; property law defines ownership condition and rights for both tangible and intangible assets, influencing aspects of municipal, land and real estate law; and international law outlines global legal matters.
Most of the world’s laws are created and enforced by government institutions. There are different types of governments, and their effectiveness in creating and enforcing the law differs widely from place to place. Even within the United States, federal laws are a small percentage of the total, with most areas left to the states to regulate and supervise. In many cases, the overlapping of state and federal law creates complex situations like when federal rules on aviation and railroads conflict with a larger body of state legislation on insurance and trademarks.