Why is null an object and what's the difference between null and undefined?

Question

Why is null considered an object in JavaScript?

Is checking

if ( object == null )
      Do something

the

Answer 1

In Javascript null is not an object type it is a primitave type.

What is the difference? Undefined refers to a pointer that has not been set. Null refers to the null pointer for example something has manually set a variable to be of type null