Evangelion Head Bust

An Evangelion (エヴァンゲリオン) is a giant human being of near-godlike power, created by NERV from samples of the First Angel, Adam (Although Eva-01 might be an exception). Evangelions were supposedly created to combat the Angel threat, although their most important function (and one of their greatest secrets) is to initiate Third Impact to evolve humanity further.

Evangelion Unit-01 (初号機[?], "Shogōki") is the first non-prototype Evangelion unit, and is referred to as the "Test Type". It houses the soul of Shinji's mother, Yui Ikari. It is the only EVA to be born from Lilith. Following its going berserker and eating

Evangelion Unit-00 (零号機[?], "Zerogōki") is the first functional Evangelion unit created, serving as the prototype for the rest of the Eva series. Although never confirmed, the soul housed in Unit-00 is implied to belong to Rei I.

Evangelion Unit-02 (エヴァンゲリオン弐号機[?]) is the third Evangelion completed, the first Production Model Evangelion. The design of Unit-02 supposedly rectifies the mistakes made during the construction of Prototype Unit-00 and Test Type Unit-01