Catechism of the Catholic Church §1242 — excerpt
In the liturgy of the Eastern Churches, the post-baptismal anointing is the sacrament of Chrismation (Confirmation). In the Roman liturgy the post-baptismal anointing announces a second anointing with sacred chrism to be conferred later by the bishop Confirmation, which will as it were "confirm" and complete the baptismal anointing.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.