Apotropaic magic

Apotropaic magic (from Greek αποτρέπειν "to ward off") or protective magic is a type of magic intended to turn away harm or evil influences, as in deflecting misfortune or averting the evil eye. Apotropaic observances may also be practiced out of superstition or out of tradition, as in good luck charms (perhaps some token on a charm bracelet), amulets, or gestures such as crossed fingers or knocking on wood. Many different objects and charms were used for protection throughout history.