The forebrain is the largest part of the brain with the Cerebrum, Diencephalon and Olfactory lobes. The forebrain is also called as Prosencephalon.
The Cerebrum: It is the largest part of the human brain. It is divided into two half parts called cerebral hemispheres by a longitudinal median fissure.
Diencephalon: It is also known as inner brain or Thalamencephalon. It is made up of three parts: Epithalamus, Thalamus and Hypothalamus.
Olfactory Lobes: They are small sized paired structures. In humans, they are poorly developed since man is less dependent on smell.