The chief exponent of this kind of law is Austin. According to him positive law is a command which obliges a person or persons to a course of conduct. It is set by a sovereign individual or sovereign body of individuals to a person or persons in a state of subjection to its author. Being a command it must issue from a determinate person or group of persons with the threat of displeasure, if the rule be disobeyed.
2. Physical or Scientific Law:
According to Salmond physical laws or the laws of science are expressions of the uniformities of nature general principles expressing the regularity and harmony observable in the activities and operations of the universe. It governs the growth of bodies, the law of gravitation, the laws governing the planetary motion, etc.
3. Natural or Moral Law:
It is that portion of morality which supplies the more important and universal rules for governance of outward acts of the mankind. In short, the law of nature is written by the lingers of nature in the hearts of mankind. It consists of the principles of natural right or wrong or the principles of justice in its widest sense.
It is also known as ‘Divine Law’ being the command of God imposed upon men, ‘Unwritten Law’ (not written on brazen tablets or on pillars), ‘Universal or Common Law’ (being of universal validity), Law of Reason (being established by that Reason which governs the world) and Eternal Law (being uncreated and immutable).
4. Conventional Law:
It consists of rules or regulations of voluntary organizations, e.g., clubs, associations, etc. Such law acquires its force or validity from the agreement between the parties concerned. It may be noted here that conventional law when enforced by the State assumes the form of positive law.
5. Customary Law:
It comprises the reasonable customs and usages observed as a right from immemorial antiquity by a particular family or by society as a whole. According to Salmond by customary law here we mean any rule of action which is actually observed by men any rule which is the expression of some actual uniformity of voluntary action.
6. Practical or Technical Law:
It consists of rules for the attainment of a practical end, e.g., the laws of health, the laws of architecture, the rules for efficient conduct of any art or business, etc.
7. International Law:
It is an aggregate of rules and regulations recognised and accepted by civilised Suites in their relations with each other. According to Oppenheim it is the name for the body of customary and conventional rules which are considered legally binding by the civilised states in their intercourse with each other.
8. Civil Law:
Salmond defines civil law as the “law of the State, the law of the land, the law of the lawyers and law courts”. It is the law of the realm and has variously been named as municipal law, positive law or national law. It is the law in the strictest sense of the term. It is the main orbit round which Jurisprudence, the science of law, rotates and forms its subject-matter.