Gamemaster's screen

A gamemaster's screen, also called a GM's screen, is a gaming accessory, usually made out of either cardboard or card stock, and is used by the gamemaster to hide all the relevant data related to a tabletop role-playing game session from the players in order to not spoil the plot of the story.

In addition, screens often have essential tables and information printed on the inside for the gamemaster to easily reference during play.

[1]: 95  The first edition version of the Dungeon Masters Screen garnered a Gamer's Choice award that year.

In the October-November 1977 edition of White Dwarf (Issue #3), Don Turnbull reviewed The Judge's Shield and found it a very useful tool, saying, "These panels contain virtually all the information needed for DM and players during a game, and moreover are much more durable than the Ready Ref Sheets.

Anybody with a photocopier, a pair of scissors, and a bottle of glue can put together a customized screen in an hour or two, so there’s little incentive to spring for the authorized version unless you’re a compulsive collector or just plain lazy.

The gamemaster's screen separates the players' view of the game (top) from the gamemaster's private information and dice rolls (bottom)
A gamesmaster (left) behind a screen