Aelita's Past Life

Aelita's family on Earth.

Aelita after being materialized for the first time.

Aelita was born to Franz Hopper and Antea Hopper. They lived in a mountain top cabin somewhere in the french Alps, but Mrs. Hopper got kidnapped by the Men In Black. After that Franz decided to move to the Hermitage where he became a teacher while he secretly kept repeating the same day over and over again to complete Xana and Lyoko. When the Men In Black began pursuing Franz, he and his daughter went to Lyoko, which, according to Hopper, was a world without danger. Before he did so, he made precautions to hide his Diary by hiding it's Key in Mister Pück, and Making sure Aelita remembered where it was. This is why in episode Mister Pück, Aelita kept seeing the elf hiding something in a tree, because it was the key to the diary. After they were virtualized, XANA, a computer entity created by Hopper to destroy Project Carthage, used the opportunity to imprison its creator and ordered the Scyphozoa to steal Aelita's memories, thus linking him, Aelita, and the fate of Lyoko to the Supercomputer . When Jeremie Belpois stumbled onto the Supercomputer and turned it on, both Aelita and Jeremie were led to believe she was an A.I. because of the fact that she had no memory at all of who or where she was, not even her own name. At first, Jeremie called her "Artificial Intelligence", but she wanted to be called something else, so Jeremie called her "Maya". Surprisingly, as stated here, she was originally planned to really be an AI and not a regular girl. After the decoding and reading Franz Hopper's diary in Revelation, Aelita found out that she was actually a real human, and was Franz's Daughter. But although the series ended, nothing (other than the fact that her mother was kidnapped) was revealed to us, this issue is presumably going to be addressed in Code Lyoko Evolution.