What is Denial, hiding the real? What is Deception, showing the false?

What is Denial, hiding the real?
What is Deception, showing the false?
How do the two relate to each other?
What are the roles of security, co-ordination and monitoring in Denial and Deception?
Why do Denial and Deception continue to succeed in spite of all that is known about them?
What are the roles of such factors as incomplete information, preconceived ideas and fears in Denial and Deception?