What is Law

Normal Law v. Positive Law

Positive law is made by people.  Natural law comes from sources that are universal.  To many people (for example, to Thomas Jefferson in the Declaration of Independence) the source of natural law is God.  Natural law is universal; it applies to everyone.  Positive law only applies to those people who are the subjects or citizens of the government that creates the law.  Positive law must be written down.  Natural laws are unwritten laws.  In short, then, positive law must be made by a given government and it relies on the government for its power.  Natural law is not made by people and has moral power regardless of whether a government recognizes it and makes it into positive law or not. According to the University of Louisiana at Lafayette, natural law refers to those laws that derive their legitimacy from moral reasoning and are based on what is believed to serve the best interests of the common good while positive laws are those that obtain their legitimacy through legislative means and are enforced by civil or political authority.

https://davegj13.wordpress.com/2010/06/12/natural-law-vs-positive-law/

What is law? 

Firstly—in all societies from primitive to the present day of highest peak of civilization-in one or other from, there is law. The difficulties not only lie in the fact of development rather in characteristics also. In different societies, ‘law’ means and includes different things.

Under Hindu Dharma—It is ‘Dharma’ 

Under Islamic—It is ‘Hukum’

Under Roman—It is ‘Jus’

Under French—It is ‘Droit’.Secondly, some defines ‘law’ on the basis of its ‘sources’. Some defines it on the basis of its ‘nature’.Thirdly—We all know that, law is a social science. It grows and develops with the society. The fast social and scientific development of modern era has created new problem. To keep pace with the society, the function and scope of law remains always changing. Therefore, it is difficult for a given definition of law at a particular time to remain valid for all times

Law is the part of established thought and habit which has been accorded general acceptance, and which is backed and sanctioned by the government of body politic. 

The law consists of the rules recognized and acted on in the courts of justice. 

Jurisprudence (Juris and prudentia) is "understanding or science of law"

Justice is the end, law is merely the instrument and the means; and the instrument must be defined by the reference to its end. 

Deciding according to pre-determined rules conveys a sense of fairness and justice.

Administering justice through pre-ascertained rules is therefore the primary function of law. 

What is Islamic law?
Sharia, Sharia law, or Islamic law is the religious law forming part of the Islamic tradition. In Arabic, the term sharīʿah refers to God's divine law and is contrasted with fiqh, which refers to its scholarly interpretations.