Offline application:

A spell, charm or hex is a set of words, spoken or unspoken, which are considered by its user to invoke some magical effect. Historical attestations exist for the use of some variety of incantations in many cultures around the world. Spells can be used in calling upon or summoning a spirit, demon, deity or other supernatural agent, or to prevent a person from taking some action or in forcing them to remain on some path of action.