What exactly is happiness, moods and states of the mind? Buddha mentioned that happiness is the greatest wealth. When going through the TED Happiness Topic, The habits of happiness, Depression, the secret we share, The struggle of mental health, All kinds of minds, How does my brain work?, What makes you happy?, etc. this left me wondering what exactly is happiness, moods and metal states in a Buddhists perspective. So what exactly is happiness? How is it the greatest wealth? How can happiness analysed using the Suttas and the Abhidhamma? How can this be extended to analyzing all moods and states of the mind?
I was always under the impression that happiness was our default setting, our buddha nature. If we remove "blow away or extinguish" all the labels, bindings, and habit energies that collect what is left is happiness. True Happiness is the default state we experience when we extinguish the fires that cause suffering. This cessation of suffering can also be described as complete peace. 

It is a great wealth because it is the only thing that can bring us true liberation.