Absolute Record
From Halopedia, the Halo wiki
The Absolute Record is a Forerunner location associated with the Janus Key. In 2558, the Librarian's stored personality on Requiem instructed Dr. Catherine Halsey to take the Janus Key to the Absolute Record. As of yet, the Absolute Record has not been explained further than Spartan Ops, and it can be debated whether it is even a physical location/place. The Librarian can be heard once more in the "Search For Halsey" episode saying "... to the Absolute Record" in response to Spartan Jared Miller questioning where requiem's aggressor sentinels were going.[1]
