Rules Cyclopedia, sid 5:
When you play the D&D game, one player will become the Dungeon Master (also known as the DM or referee). He or she will create the world and setting in which the adventures will be taking place and will create a variety of char- acters to populate the world. The DM will also develop situations taking place in that world and will then run adventures—acting as the main narrator of the stories in which the other players' characters will participate.
The other players will create characters—the heroes of the DM's story. The DM will present their characters with situations, and they'll de- cide how to react to those situations. Several situ- ations progressing toward a conclusion become an adventure or story; a number of adventures played one after another become a campaign.
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A table is normally used, the DM sitting at one end with information about the dungeon. The DM often uses an upright piece of stiff card- board (called a screen) to hide the description and maps of the dungeon so they are not acci- dentally seen by the players.
The players sit around the table, away from the DM, where they can all easily see any maps made during the adventure, the order of the fig- ures (if used), and so forth.
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In this section of the book, we're going to de- scribe everything needed to know in order to create a. player character—a character played by any player except the Dungeon Master.
Jag tolkar detta som att DM är en spelare av spelet, sedan säger man "other players", och efter det gör man en tydlig definition av "player character", men inte av begreppet "player". Det bästa jag kan göra av det är att om man spelare D&D är man antingen
DM, eller
spelare en player character