Primitive value vs Reference value

Question

I read a book called \"Professional Javascript for web developer\" and it says: \"Variable is assigned by Reference value or Primitive Value. Reference values are objects st

Answer 1

A variable can hold one of two value types: primitive values or reference values.

• Primitive values are data that are stored on the stack.
• Primitive value is stored directly in the location that the variable accesses.
• Reference values are objects that are stored in the heap.
• Reference value stored in the variable location is a pointer to a location in memory where the object is stored.
• Primitive types include Undefined, Null, Boolean, Number, or String.

The Basics:

Objects are aggregations of properties. A property can reference an object or a primitive. Primitives are values, they have no properties.

Updated:

JavaScript has 6 primitive data types: String, Number, Boolean, Null, Undefined, Symbol (new in ES6). With the exception of null and undefined, all primitives values have object equivalents which wrap around the primitive values, e.g. a String object wraps around a string primitive. All primitives are immutable.