Joke:
Happiness is nothing more than good health and a bad memory.
A pun is a humorous use of words, it’s a play of words:
I went to the dentist without lunch, and he gave me a plate.
In internet I’ve find many webs about happiness. There are different fields: psychological studies, means of happiness, films about happiness, songs, books, the way for getting happiness, even we can find a club of happiness.