Curse is the opposite of Blessing. Curse is like a poison tablet injected in the energy field of a person and gradually it dissolves in your energy to lead you into the dark by creating misfortune or accidents or sheer lack of happiness. It is all dependent on your inner power, openness in the energy of the person who is being cursed (which often the case is) that the Curse will be effective or not and it is just matter of time.