The majority of people around the world are affected by some form of mental disorder which can affect their quality of life. In North America alone there are more than 1.2 million people who suffer from one type or another of mental disorder, according to the American Psychological Association. Among the most common types of mental disorders are anxiety, depression, bipolar disorder, alcoholism and substance abuse. However, this does not necessarily mean that every person who suffers from one or more of these disorders will have the disorder in the future, nor does it mean that each of these disorders is necessarily a mental disorder. In this book I breifly describe the most common mental health disorders affecting society.