Zero-One, designated as Q9-01, represented a Q9-series astromech droid and incorporated a vocoder. During the Yuuzhan Vong War, Zero-One functioned as the astromech droid specifically assigned to Kyp Durron. Kyp obtained him from a Mon Calamari philosopher who held a deep interest in past civilizations and their technologies. This philosopher's great admiration for a binary-based computer system led him to name the droid using the numerical values "0" and "1".