National law is the body of laws that exist in a nation (State) and emanate from its legal authority. These can come from decisions made by judges or enacted by the legislature.
Common law is the primary source of national law in England, Ireland, Malta and many other former colonies. It is derived from the Anglo-Saxon law tradition, and includes the doctrine of stare decisis.
Generally speaking, civil law systems are more formalized than common law. They are codified in a formal written code that provides a system of rules and procedures for judicial proceedings.
They include the law of contracts, property and other private matters. They also include criminal law and administrative law.
Some jurisdictions have a mixture of common law and civil law. This can be seen in Canada, where both English common law and French civil law are used to govern different aspects of life.
The United States is a federal system of government, with power divided between a national government and state governments. Its Constitution, signed by George Washington in 1789, grants the national government the power to enact laws that must be passed by both houses of Congress and be approved by the president.
In this country, there are three different types of laws: federal laws, individual laws and regulations. The first type are bills that have passed both houses of Congress and been approved by the president. The second type are laws that have been enacted by individual states.