In many cultures, breaking a mirror is believed to bring seven years of bad luck.
A common superstition is knocking on wood to prevent bad luck from coming true.
Many believe the evil eye can curse others with misfortune. Amulets protect against it.
In Japan, the number 4 is avoided due to its pronunciation being similar to "death."
In several countries, walking under ladders is thought to bring misfortune or bad luck.
Spilling salt is unlucky, but tossing it over your shoulder wards off bad spirits.