  Dendritic cells are the crime scene investigators of the human immune system.
Their function is to correlate potentially anomalous invading entities with
observed damage to the body. The detection of such invaders by dendritic cells
results in the activation of the adaptive immune system, eventually leading to
the removal of the invader from the host body. This mechanism has provided
inspiration for the development of a novel bio-inspired algorithm, the
Dendritic Cell Algorithm. This algorithm processes information at multiple
levels of resolution, resulting in the creation of information granules of
variable structure. In this chapter we examine the multi-faceted nature of
immunology and how research in this field has shaped the function of the
resulting Dendritic Cell Algorithm. A brief overview of the algorithm is given
in combination with the details of the processes used for its development. The
chapter is concluded with a discussion of the parallels between our
understanding of the human immune system and how such knowledge influences the
design of artificial immune systems.
