A ‘Shaytaan’ can live among human beings or Jinns, for these two beings alone have been bestowed a ‘free will’ to choose between obedience and disobedience of their Lord among all His creations. All those among the Jinns and the human beings who follow the mission of disobedience of Iblis, the first Shaytaan are all termed Shayateen by Allah. Shaytan can be used to refer to anything that harms or opposes you, such as harmful bacteria or viruses.