Appears In: Uru: Complete Chronicles, Uru Live
The KI was originally named (or at least, labeled) as such by the D'ni because it served three basic functions when it was invented: communication, Marker-related functions, and Nexus access.
KIs can be used to communicate with other individuals in the same Age or in different Ages through the use of a text chat system, similar to text messaging on cell phones. They also support that creation of notes and photographs, which can be sent to other users using what has been cleverly termed "KI-mail", and can also be uploaded to various imagers in the Neighborhoods.
The KI is also critical to the calibration and continued maintenance of the Great Zero through the use of Marker Missions. Calibration is performed by comparing a Marker's actual location in the Cavern with where it is supposed to be according to records stored by the Great Zero. By collecting enough Markers, the Great Zero can self-correct its alignment and function properly, enabling the use of a cylindrical coordinate system (elevation, angle, distance) referred to as "KI-PS", or KI Positioning System (similar to Surface GPS, or "Global Positioning Satellite, systems). Explorers who have sufficiently calibrated their KI to communicate with the Great Zero can create Marker Missions of their own, which can be sent through the KI-mail system to other explorers.
The KIs are also designed to integrate with the Nexus, a massive linking hub Age offering access to the Neighborhoods, Ae'Gura, the City Proper, and all registered Ages in the D'ni empire, provided you have permission to access the Book. Each KI maintains a list of Ages and Cavern locations that its wearer is allowed to access. When inserted into the [article title=Nexus Book Machine]Nexus Book Machine[/article], this list is displayed graphically, allowing an individual to select their desired destination. In public locations such as Ae'Gura, [article title=Nexus Terminal]Nexus Terminals[/article] allow users to "register" additional link-in points by inserting the KI into a slot beside the Nexus Linking Book. These additional locations then appear on the Nexus Book Machine list.