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                //  JavaScript has Dynamic Typing:  data types are automatically assigned to variables.  It can figure out the data type.
// Variables cannot start with symbol or number
// Variables can start with $ or _
// Cannot use reserved JS keywords as variables

// Strings
// using single quotes for looks
// using camelCase notation
var firstName = 'Don';

// Numbers
// js numbers are all floating point numbers
var age = 50;

// Boolean
// True or False 
var fullAge = true;

// Undefined
// No Values assigned yet
var job;

// Null
// non-existent