I am loving this series about the benefits and purposes of play.  We can all learn from the young animals!

Professor Ben Garrod is one of the main contributors to explain the defining characteristics of play:

Relaxed state; repetition; no goal, the endorphin high is reward in itself; voluntary; early in life;  prepare for the unexpected

But all human mammals wanting to learn use the same techniques – the repetition until it becomes second nature; the pleasure and relaxation when the skill is mastered at last; the need for fun.

I will add more to this when I have seen second programme and have a bit more time.