Law is a system of rules that regulates the behavior of a community, country, or society. It is used to protect the rights of citizens and the interests of business.
Definitions by Wiktionary
The term law means a rule of conduct prescribed or established by authority, or by custom. A rule of behavior that should be followed by all members of a society.
A rule of action prescribed by the supreme power in a state, commanding what its subjects should do, and prohibiting what they must not do; a statute.
Statute law, the written laws of a government, usually in the form of a constitution or laws of the land; also, any collection of such statutes and enactments establishing a body of rules to be observed by the inhabitants of a certain territory or state: the statutes of the United States.
Cases are court decisions (or opinions) which have become precedents, that is, they should be followed if a similar situation arises again. These cases are found in collections called casebooks, which present them lightly edited or whole so that first-year students can hone their case-analysis skills.
Periodicals
Legal periodicals are local or national journals published at different times and covering a wide variety of legal topics. They are primarily law reviews, but also include specialized and scholarly journals; bar association journals; commercial journals in specialized fields; and legal newspapers.
Conclusion
Secondary resources do not establish laws, but are useful for discussing and explaining them. These sources can be helpful when locating primary sources and determining whether the law was established.