Difference between Configurable and Writable attributes of an Object

Question

I saw the following regarding javascript, object data property attributes

— 
Configurable: Specifies whether the property can be deleted or changed.

— Enume

Answer 1

From: http://ejohn.org/blog/ecmascript-5-objects-and-properties/

Writable: If false, the value of the property can not be changed.

Configurable: If false, any attempts to delete the property or change its attributes (Writable, Configurable, or Enumerable) will fail.

Enumerable: If true, the property will be iterated over when a user does for (var prop in obj){} (or similar).