Null_Undefined.js

/*JavaScript types can be classified into 2 categories: Primitive and Objective
  Primitive types include:
    numbers
    strings
    booleans
    symbol
    null
    undefined 

  Non primitive types are objects.  
    Object types have properties and have methods that can act on those properties.

  Primary difference is that primitive types store one value, while object types store many properties. 
  In addition, primitive types are passed by 'value' and object types are passed by 'reference. 

  Arrays are not a type in JavaScript. Arrays are objects. 
*/


/*JavaScript defines two special types, which both have only one value assigned: null and undefined.

Null is a special value that indicates the 'absence' of a value. (defined as None in Python)

Undefined indicates that a variable has not been initialized and the value is absent.

It’s commonly returned by functions with no return value. Example, when a function accepts a parameter
that’s not set by the caller, this results in an undefined error. 

*/