Its purpose is to enhance a player's "permission to believe" by providing an opportunity to enjoy an informed glimpse from behind the scenes and to develop an appreciation of the thoughts, ideas, technology and processes used to develop the game. Developer commentaries also include specific facts pertaining to the game's canon touch points; for example, one commentary states that Francis is six-feet five-inches tall. The following pages provide more in-depth coverage of the developer commentaries in each game: * Developer Commentary (Left 4 Dead) * Developer Commentary (Left 4 Dead 2)