Positive psychology is often referred to as 'the scientific study of happiness.' Originating in the States almost twenty years ago, it has steadily been gathering evidence about what the exact actions a human can take in order to be happy.

But what do we mean by 'happy'? It is a word with many meanings within it, some which appear to be contradictory. So it is important to make clear the exact type of happiness that positive psychology concerns itself with.

Positive psychology separates happiness into two broad camps: there is 'hedonic' happiness, and there is 'eudaimonic' happiness. Hedonic happiness could be described at relative sort of happiness. It is the type of happiness that depends very much on our immediate circumstances and our environment. You could call it a reactive happiness. It is the happiness we might experience as a result of a great meal, or funny film, or holiday or shopping trip. The basic attribute of hedonic happiness is that it does not last very long. It comes, it goes, it wears off.

The second type of happiness, eudaimonic happiness, could also be called absolute happiness. It can exist independently of our immediate circumstances and environment as it very much comes from within ourselves. This is a more consistent type of happiness. It is the happiness we are aware of when we are able to stay optimistic and cool in a crisis, it is the happiness that is experienced as an undering feeling of contentment and strength that persists throughout the ups and downs life throws at us.

Positive psychology's interest lies with the second type of happiness. With eudaimonic happiness. This is the happiness that lasts and lies within our control: we can take actions that will directly and without fail invest in our reserves of this type of inner happiness, and science has now demonstrated this as a fact.

So how is it done? Positive psychology begins by exploring the five key ares of our lives in which our eudaimonic happiness can be developed, and calls this the PERMA model. PERMA is an acronym for the areas which require our attention and investment if we are to create more happiness in out lives. These areas are: Positive Emotion, Engagement, Relationships, Meaning and Achievement.

In the rest of this How to be Happy article series, we will explore these areas further and take a look some of the practical actions we can all take to invest in our eudaimonic happiness.