The definition of mental illness as defined by the Australian Institute of Health and Wellness is the following: a clinically diagnosable disorder that significantly interferes with a person’s cognitive, emotional, or social abilities. 

1 in 5 adults in Australia experience a mental illness every year with it being estimated that 45% of Australians will be affected by mental illness at some time in their life. As with many diseases, there is a spectrum and, in some people, it can be severe and noticeable and in others mild and not noticeable. There are many different types of mental illnesses including depression, anxiety, obsessive-compulsive disorder (OCD), schizophrenia, and bipolar disorder. Each illness can alter the persons’ thoughts, feelings, and behaviours in distinct ways with specific characteristics being related to a type of mental illness.