Authentic happiness... Opposed to what?

So while googling Authentic one of the first things you come across is "authentic happiness". Cuz when I am happy its definitely no authentic. Here is the intro to the site:

Dr. Martin Seligman is director and founder of the University of Pennsylvania Positive Psychology center a new branch of psychology which focuses on the empirical study of such things as positive emotions, strengths-based character, and healthy institutions. His research has demonstrated that it is possible to be happier — to feel more satisfied, to be more engaged with life, find more meaning, have higher hopes, and probably even laugh and smile more, regardless of one’s circumstances. Positive psychology interventions can also lastingly decrease depression symptoms. The research underlying these rigorously tested interventions is presented in the July/August edition of the American Psychologist, the journal of the American Psychology Association.

Authentic Happiness has almost 700,000 registered users around the world. You are welcome to use all of the resources on this website for free.