What are sacramentals in the Catholic Church?

Sacramentals are sacred signs (objects, actions, or blessings) instituted by the Church that bear a certain resemblance to the sacraments but differ in an important way: while sacraments confer grace directly by the power of Christ (ex opere operato), sacramentals dispose the faithful to receive grace and sanctify various occasions of life through the prayer of the Church (ex opere operantis — depending on the disposition of the recipient). Common sacramentals include: (1) Blessed objects — holy water, crucifixes, rosaries, medals, scapulars, statues, and blessed candles. (2) Actions — the Sign of the Cross, genuflection, bowing, sprinkling of holy water. (3) Blessings — of persons, meals, homes, vehicles, and religious articles. (4) Exorcisms — prayers of deliverance from evil. Holy water is perhaps the most frequently used sacramental, reminding the faithful of their baptism and providing spiritual protection. The Catechism states that sacramentals 'prepare us to receive grace and dispose us to cooperate with it' (CCC 1670). They should not be treated as superstitious objects but as aids to devotion that draw their power from the prayer of the Church.