The three major parts of the brain are :

(1) Fore-brain, 

(2) Mid-brain and 

(3) Hind-brain. 

The major parts of the brain and their functions are as follows:  

(1). Fore-brain - It is the main thinking part of the brain. It has three main parts-the olfactory lobes, the cerebrum and the diencephalon.  

(a) The olfactory lobes - These are a pair of very small club-shaped bodies which are fully covered by the cerebrum. They act as a center of smell.  

(b) The cerebrum - It is the largest and most prominent part of the brain. It is divided into right and left cerebral hemisphere by a deep groove. It is the center of consciousness, thoughts, memory and analytical thinking. It also controls voluntary actions.  

(c) Diencephalon - It mainly consists of pituitary gland, hypothalamus and thalamus. It posses control unit of thirst, hunger, temperature, sleep, etc.

(2). Mid-brain - It acts as a coordinating unit between forebrain and hindbrain. It also controls some involuntary actions.  

(3). Hind-brain - It has three main centers - Cerebellum, Pons and Medulla oblongata.  

(a) Cerebellum- It is responsible for precision of voluntary actions and maintaining the posture and balance of the body.  

(b) Pons - It is the center through which nerve impulses travels to and from the cerebellum, spinal cord and other parts of the brain. It also helps in respiration.  

(c) Medulla oblongata - It is the lowermost part of the brain. It contains vital centres for controlling blood pressure, respiration, swallowing, sneezing, coughing, salivation and vomiting.