The memory device in the Assassin’s Creed series is called the Animus.
The Animus is a fictional machine that lets a user experience genetic memories inherited from ancestors. In the early games, Desmond Miles uses it to relive the lives of historical Assassin ancestors, including Altaïr Ibn-La’Ahad and Ezio Auditore. The device provides the narrative link between modern-day characters and historical settings.
The concept does not mean that the user travels physically through time. Instead, the series presents the experience as a technologically reconstructed memory. This distinction is central to the franchise’s science-fiction framework and explains why modern-day scenes appear alongside historical gameplay.
The term is sometimes confused with Helix, which is a later entertainment and memory-experience platform in the series’ fiction. Eagle Vision is an Assassin ability rather than a machine, while the Apple of Eden is a Piece of Eden with different properties. These are separate concepts even though all are important to the wider lore.