World

The setting of Citadel: an ancient machine larger than memory, and the people living inside it.

The Citadel	The megastructure itself and what is known about it.
The Derailment	The catastrophe that followed the halt of DAAT.
Mainframe	Humanity's known world: three strata, city-states and frontier.
Breachers	The crews who force passages into sealed regions.
Factions	The powers fighting over Mainframe.
Machine intelligences	Mathrons, daemons, golems, ghouls and morning stars.
Security circuits	The staged response that defends protected zones.
Aberrations	Organisms that are living beings and machines at once.
Timeline	Dated events, from Clement to the Credit Revolution.