Law is an ordered system of rules developed and enforced by governmental or social institutions to govern behavior, having its precise definition subject to ongoing debate. In some sense, law is an attempt to define who we are and what kind of behavior is acceptable. In other ways, the law is an effort to prevent or deter crime. It is also used to determine who among us has jurisdiction to claim certain entitlements, rights, and privileges and for other purposes such as immigration, property rights, and others. It has likewise been differentially defined as both an art and science of law.
Law thus refers to the practice of law pursued by lawyers, judges, and other attorneys. Within the body of law that results from the judgments of courts and juries are disciplines such as criminal jurisprudence, corporate law, family law, international law, labor law, environmental law, family issues, land law, tax law, and other specializations. The jurisdictions in which these bodies of law are practiced vary considerably from one state to another.
Jurisprudence is that branch of law that concerns itself with legal cases regarding the courts and criminal laws. Criminal laws are those sets of rules that provide punishment for the commission of crimes, irrespective of whether the crimes are classified as federal, state, or local. Criminal jurisprudence therefore covers the penal code and case law that have been derived from the state or federal governments and their organs such as the Department of Justice, the Bureau of Alcohol, Tobacco, and Firearms, and other relevant state agencies. There are also instances where criminal laws will be considered foreign jurisdiction.
Civil law is that branch of law that deals with disputes between individuals, organizations, or the state and its agencies. Civil law is governed by a variety of systems including customary law, the universal law, and customary international law. In Europe, there are many branches of civil law including domestic law, European law, and human rights law. Most national courts of important significance to operate in Europe. For instance, the European Court of Human Rights, the European Union, and the ECDU provide high-level court structures that are largely derived from customary international law.
Judicature is the supreme court of appeal and is the highest court of a country. The U.S. system is administered by the Supreme Court, and decisions by lower Federal Courts are derived from the decisions of this Court. Unlike the various branches of civil law, there is no common law in the United States. Because of this, the powers that are vested in the U.S. Judicial Branch is more limited than in many other countries.
Taxation is the collection of revenues from citizens for the support of public purposes. Taxation is heavily influenced by the various kinds of taxes that are assessed. Common law has been replaced by modern common law in tax matters. Many civil and criminal laws are derived from the common law in some form.
Property law deals with the buying and selling of personal and corporate property. Civil laws deal primarily with things like injuries and damages to individuals. Criminal laws deal with things like felonies and crimes. Many U.S. states use hybrid systems of taxation, and most of these hybrid systems of taxation are highly influenced by things like property law.
The U.S. system is heavily influenced by things like tort law, which is the area of civil law that deals with lawsuits against corporations or individuals for harms that occur through the negligence of other individuals. Personal injury laws can also affect corporations and individuals. In order to understand the different areas of law in the United States, you must first understand the differences between civil and criminal law. In order to learn more about civil and criminal law, I recommend that you research the various universities that offer courses on the subject matter.