A designed experience in which a set of rules balances chance and/or the skill of other participants with a player’s decisions. A game model laid out by the Danish game designer and theorist Jesper Juul balances the restrictions of successful game interfaces with the flexibility required for play: “1) a rule-based formal system; 2) with variable and quantifiable outcomes; 3) where different outcomes are assigned different values; 4) where the player exerts effort in order to influence the outcome; 5) the player feels emotionally attached to the outcome; 6) and the consequences of the activity are optional and negotiable.” Games may be social in nature or solitary, but play is the focus in either scenario.