title: What is the "symbol" primitive data type in JavaScript
body: <p>The new primitive type comes with ES6 which is Symbol type.The short definition says :</p>
  
  <p>A symbol is a unique and immutable data type and may be used as an identifier for object properties. The symbol object is an implicit object wrapper for the symbol primitive data type.</p>
  
  <p>I did some research but I cannot understand why we need this primitive type exactly?</p>
  
  <p>Thank you for your answers.</p>