State Unconscious is a term used to describe a medical condition in which a person is unable to respond to stimuli or communicate with others. It is usually caused by a severe injury or illness, and can be classified into two categories: COMA and vegetative state. COMA is a state of deep unconsciousness in which a person is unresponsive to external stimuli and cannot be aroused, even by painful stimuli. A vegetative state is a state of partial consciousness in which a person is awake but unaware of their surroundings and unable to interact with others.