The concept of natural rights was first proposed by an English philosopher called John Locke. He emphasized there factors known as Life, Liberty, and Property as being the core of independence and should be non-negotiable or sacrificed for anything.
This was adopted in the Declaration of Independence of the United States from Great Britain on July 4, 1776.
They are man made barriers, made of sand, to protect the coast from erosion from the incoming waves. They also help to control flooding from storm surge.
