Law is a body of rules that govern social, political and economic relationships. It has many purposes, including maintaining the status quo, preserving individual rights, protecting minorities from majorities and promoting social justice and order. Different countries have different laws, and some serve these purposes better than others. For instance, authoritarian governments use the law to suppress political opponents and minority groups. In common law jurisdictions, law is created by a legislature or executive, but it can also be created by private parties in the form of contracts or arbitration agreements.
There are many types of law, including common and international law. International law, for example, focuses on the rights of foreign nationals to reside and work in a nation state. It also deals with the right of asylum and the issue of statelessness. Other areas of law include tax law and financial regulation. Tax law deals with value added tax and corporate and income taxes. Financial regulation deals with investment, business, and financial matters.
A constitution is often used to govern the practice of law. It aims to provide guidelines and limits on power allocation and define the relationship between the government and its citizens. However, no constitution can guarantee against effective usurpation, which is why many countries blatantly ignore their constitutions. The constitutions of many countries are merely a collection of case law, custom and compromises.