Central Nervous System (CNS)
CNS is a term that describes the brain and the spinal cord. This is a term you are probably familiar with, since it is one of the most commonly used scientific terms around. Despite this, there is some small debate about the CNS - some claim that the retina is also part of the CNS. However, the most accepted view is that the CNS contains only the brain and spinal cord, and that the retina is part of peripheral nervous system.