The player is directly and immediately aware of all the information that is relevant to make decisions or choices within the game. The only aspects which may be unknown are those that are dependent on chance or on the decisions of other players.
In the board game Chess, each player is aware of the exact location of all the pieces on the board.
In PacMan, the player can see the entire maze, the location of all the enemy ghosts, his current score, the location of all the dots that still need to be eaten. There is no information relevant to making decisions that is obscured from his view.
Fire Emblem: The Sacred Stones
In Fire Emblem: The Sacred Stones, the player may examine the full stats and equipments of all units on the field, be they ally or enemy. Before each player-made attack, the game also displays the probabilities of the outcome of the battle, although these all operate on a strict set of formulae that the player may infer if they know how it functions.
In Advance Wars the game can be played with or without fog of war--a feature prominent in RTS's which obscures Complete Information.