DIKW is the ITIL v3 interpretation of Knowledge Management. Represented as a growth path for "understanding", the concept is a good one in that it builds on the traditional view that data (D), becomes more valuable once it is processed into information (I).
DIKW then shows how information becomes the basis for knowledge (K). Knowledge is a collection of experience and ideas and is the element required to understand HOW an activity should be performed.
The final and ultimate piece of the DIKW model is wisdom (W). Wisdom is the pinnacle of understanding and permits a rational answer to the greatest question of all - WHY?.