The Animus is the secret research device used by Abstergo in Assassin's Creed.
In the series, the Animus allows a user to access genetic memories inherited from ancestors. The device converts those memories into an interactive experience, allowing modern characters to witness and, in some versions, participate in events from the past.
Abstergo Industries uses the technology for research and strategic purposes, while the modern Assassin Brotherhood seeks to understand and counter that work. The first game introduces the Animus through Desmond Miles, who is forced to relive the memories of Altaïr Ibn-La'Ahad.
The term is sometimes confused with Helix, a later Abstergo entertainment platform featured in Assassin's Creed Unity. Eagle Vision is an Assassin ability rather than a machine, and an Apple of Eden is a Piece of Eden artifact. These are related elements of the fictional universe but are not interchangeable names for the device.