Why is there a mental health section and a psychology section? explanations please?

Psychology is a: Specialization w/in mental health. There are social workers, counselors, psychiatrists, nurse practitioners, etc. Who all work in mental health. Each brings a unique twist to the field and they all overlap. Psychology also refers to research and the whole field of human behavior, not just therapy. Hope that helps.

Mental health: Mental health is pertinent to many medical specialties, because it can affect the illnesses each covers as well as patients' ability to work with treatment. Psychologists, psychiatrists, social workers, etc are all professionals working in the area of "mental health." so "mental health" is a large umbrella topic vital to overall health. Psychology is merely one area within that.

Field: Psychology can be thought of as the whole field which means experimentation, research, psychotherapy, consulting, testing, evaluations and many other different functions. Mental health can be thought of as a subset of the field as a meh ole where counseling or psychotherapy is practiced.