The scientific process of knowing the human mind as well as its behaviour is known as psychology whereas the branch of medicine that deals with the emotional and the metal illness is known as psychiatry.
Rudolph Gockel was the person who developed the name of psychology. Psychologist is a scientist or a clinician who investigates the mind of the human which includes their cognition and behaviour as well. Some of the major fields of study are research psychology and clinical psychology and a licensed practitioner must be a PhD, PsyD or EdD.
The name psychiatry was developed by Johann Christian Reil and a psychiatrist is a physician who helps to treat the mental illness. MD or DO are the licensed practitioners in the field and major field of study are psychiatric medication & Tomography.
As per the year 2010, out of every 5 Americans, 1 suffered from the problem of mental illness. 16.9 % of Men were diagnosed with mental illness whereas more than 23% of the women suffered from the mental problem. As compared to the people above the age of 50, the rate of mental illness among the youth adults in the age group of 18 to 25 years is twice more.