Cartographer (Earth-2915)

The Cartographer is a dedicated forerunner facility designed to contain and provide access to the Silent Cartographer, a program featuring the complete real-time record and schematics of an installation. A central component of any installation of forerunner construction, it is found on nearly all of their megastructures, such as the Halo Array and the shield worlds. Some installations contain a number of discrete Cartographer facilities.

When activated, a Cartographer provides a real-time holographic map which can be used to navigate the massive expanse that is an installation, along with other relevant information such as pinpointing every room or location within the vast structure. The Cartographer facilities on the various Forerunner installations differ in layout and design, though the primary map rooms on the Halo installations are buried within large structures housing a network of compartments and rooms. Due to their significance, the Cartographers are protected by multiple security measures.

An artificial intelligence is able to interface with the Silent Cartographer and, for example, set navigation points on the holographic projection.

Source

 * https://www.halopedia.org/Cartographer