There are many shades of happiness...
There is the kind of happiness that is the 'fist-pump' type, usually accompanied by a "Yes!". This is coming from the ego, and its all about getting something, and one's own personal experience. Then there is soul/spirit happiness that includes being happy with and for others - and thirdly there is a kind of happiness that is perhaps better described as joy, that emanates from somewhere beyond...it just arises as if from nowhere.
The egoic mind/body sense of happiness comes when we feel deeply satisfied or we achieve a goal or gain something, or perhaps during a moment of excitement. This type of happiness is always associated to an 'object', whether physical or mind-made. It is short lived and unreliable, and constantly in a state of flux. It can disappear or turn into despair in a blink of an eye.
A deeper form of happiness comes from beyond the mind, for example from the profound connection formed in an enduring relationship that is founded on trust, respect, love, or it can have its roots in the gratitude and appreciation of a beautiful experience, a glorious sunset, being in the company of true friends. This kind of happiness is more stable because it is not entirely dependent on the external aspect although it is prompted by one, and it can be seen in you and even experienced by others when they see it in you or are around you.
The third kind of happiness is much rarer and has to be experienced to be known. We all do glimpse it occasionally - a kind of profound peaceful moment that is beyond words to adequately describe, but we know intuitively it is not connected to any particular external object or event. We know it comes from within, deeper than we can explain, and always when there is a still peacefulness inside, when the mind has briefly stopped. This happiness comes as joy, a feeling of love and openness - it can even bring tears - it is 'pure happiness', not associated with anything in particular.
When this comes, it is a sure sign you have tasted the essence of your truth, the absolute self as it is.