The document discusses definitions of play, games, toys and puzzles. Play is defined as voluntary and intrinsically motivated activity, while a game is play with a goal. A toy is an object used during play and a puzzle has a dominant strategy. The document also discusses theories of play from Huizinga and Callois. Huizinga saw play as distinct from ordinary life, while Callois identified four categories of play: agon, alea, mimesis and ilinx. Finally, the document discusses what makes a good game, including interesting choices, understanding patterns, and achieving flow. It argues the entire game experience is important, not just individual elements.