A position is a division of the Stage used as a map in interaction scenarios. Depending on the scenario, an individual position may represent a part of a room, a broader area, a conversation topic, or other abstract considerations.
Positions are linked together with connections that form the Stage. Entities each occupy a position and may Move across connections between positions, though Charisma can often be used to block such movement. Some entities may, at the DM's discretion or scenario's design, occupy multiple positions at once.
For more information, see Player's Guide Chapter 6: Interaction.