In Assassin's Creed, the Animus lets modern people relive ancestral memories.
The Animus is a fictional machine that reads genetic memories inherited through a person's lineage. In the first game, Desmond Miles is forced to use it so Abstergo Industries can access the memories of his ancestor Altaïr Ibn-La'Ahad. The machine creates the game's central link between a contemporary storyline and historical episodes.
The Animus does not send a person physically through time. Instead, it reconstructs experiences from ancestral memory, allowing the user to observe and participate in a simulated past. Later games introduce upgraded Animus systems, portable versions, and entertainment-oriented products such as the Helix platform.
The Animus is often confused with Pieces of Eden, especially the Apple of Eden. Pieces of Eden are powerful ancient artifacts within the story, whereas the Animus is the technology used to access memories connected to them.