A game of skill is a game
A game of skill is a game where the element of chance has been utterly eliminated. Examples are Chess, Checkers, and Teeko, a skill game which I invented myself. (If you happen to like skill games, you should love Teeko.) In these games the skilled player will invariably win against an unskilled opponent, and the skilled player's winning percentage will be an exact reflection of the relation between his ability and that of a less skillful opponent.
A game of chance is a game
A game of chance is a game from which the element of skill has been eliminated (unless you assert that cheating is a form of skill!). Games of chance number thousands. Examples are Roulette, wheels of fortune, and most of the dice games such as Private and Casino Craps.