Happiness can be expressed trough many things. It can be also expressed trough many colours. For me,the colour that represents this feeling  is yellow and there's a lot of reasons why.
Yellow represents excitement and joy. It's the feeling you get when you see a field full of yellow flowers while you're in a car or in a park on a spring day. It represents the happiness in life that a important person,pet or your favourite book can give you. It's the happiness that comes from simple things we do and enjoy,like singing, dancing or playing.
Yellow is a very pure colour and it represents the happiest moments in my life.