The human brain is made up of two types of matter the outer grey matter and inner white matter.
Grey matter is nothing but it is due to collection of cytons/cell bodies/soma of neurons and non-myelinated neurons which appears grey in colour hence called grey matter.
White matter is due to collection of myelinated neurons hence called white matter.
Outer grey matter and inner white matter is present in cerebrum, cerebellum while outer white matter and inner grey matter is present in pons, medulla oblongata and spinal cord.
