I am still in the process of researching fun – but it has been really interesting so far. If you have no taken my quick survey – please do, it will really help me!! – Fun Survey
The thing that is abundantly clear is that fun is purely subjective, what one person finds fun – others may think is a waste of time. The Oxford English Dictionary defines fun as
Enjoyment, amusement, or light-hearted pleasure
In the study I have done to date, so far I have identified about 21 distinct things that people feel fills this definition for them.