Human sacrifice is the act of killing one or more human beings, usually as an offering to a deity, as part of a religious ritual. Its typology closely parallels the various practices of ritual slaughter of animals and of religious sacrifice in general. Human sacrifice has been practiced in various cultures throughout history. Victims were typically ritually killed in a manner that was supposed to please or appease gods, spirits or the deceased, for example as a propitiatory offering, or as a retainer sacrifice when the King’s servants are killed in order for them to continue to serve their master in the next life. Closely related practices found in some tribal societies are cannibalism and headhunting.