Mental ill health is often described in a number of ways; mental illness, mental health problems, mental difficulties, mental distress, emotional disorder, nervous breakdown and mental break down.
There are some other less constructive, slang terms like; psycho, crazy, mad, loony, wacky among others which are derogatory, stigmatising and generally should be avoided when confronted with someone struggling with their mental health.
The aforementioned terms are quite vague and do not convey much about what it is exactly the person is experiencing. To clarify; a mental illness disrupts a persons behaviour, emotions and their thinking, while affecting their ability to function in their day to day lives, their work and their interactions with other people.
Some people with only have one bout or episode of mental illness their lifetimes, while others have periods of wellness punctuated by recurrent episodes of mental illness, often called relapses. To a lesser degree, there are also people who consistently struggle with their mental health and have an ongoing condition or problem.
The common types of mental illness include depression and anxiety disorders, there are also less common ones such as bipolar, schizophrenia and personality disorders.
The key point to remember about mental illness, is that they can and do cause disability within the person struggling their mental health, which can often severely affect their lives and affect their ability to function. This is often misunderstood by individuals who have not experienced a mental illness.
A mental health issue and mental ill health are often broader terms which can be used to describe someone presenting some symptoms of a mental illness but is not severe enough to diagnose the person with one.