Define Fun

My definition of fun is anything that makes you happy. So happiness can be caused by a vast number of things depending on the person;

• Watching a movie/tv
• Playing a game (computer/physical)
• Eating (for some people)
• Shopping (mostly females)

There can be a lot more reasons for happiness in a person. 

So having fun is up to the individual, he/she should figure out what makes them happy and do that.