Entertaiment is the art of amusing oneself with the requisite minimum amount of effort and expenditure. It is not to be confused with frivolous and debauchery. A good example of this would be a day out at the park or an evening spent in the great outdoors, where the requisite minimum amount of effort and expenditure are required. A worthy contender for a day out at the park or an afternoon of outdoor shenanigans where the requisite minimum amount of effort and monetary spend are required, is an evening of ad-libbed fun.