Most of this materialistic world thinks of happiness as having everything you ever wanted like an expensive car, money, the best clothes, fancy homes... but that doesn't really fulfill one's needs and more of their desires/wants. Simplicity is the key when you are striving for happiness. You will always have a moment of happiness at least once or twice in your life, but I think that the catch with happiness is exactly that.
For me, happiness is eating pizza (and not having to share) while my dog sleeps on my lap and my best friends are over watching a funny/scary movie together while we laugh our butts off until our stomachs start hurting. I realize that it isn't the movie or the food that made me happy though... I think it was just sharing that good company and quality time with friends because when people are around then you get a sense of home I suppose because home is somewhere you feel free and be around people you like.
One can never have their whole life not experienced one meer moment of sorrow or struggle in their life. With that said, happiness is no more than a feeling in a moment in time because it doesn't last forever. i think that the things that make people happy are hat they take for granted most in life. I actually do that myself to be truly honest... I feel like we are thinking about happiness in the wrong way and it really gets us confused with what makes us truly happy.