Botnet
This is the term given to a collection of Bot or Zombie devices that are under the control of a Botnet Controller. Botnets are predominantly used to support spamming, although there are numerous examples of Botnets being used to launch DDoS attacks. The major problem with Botnets is the sheer scale of them; it is not uncommon to hear of Botnets that are comprised of hundreds of thousands of Bots. Many Botnets have a link to organized crime syndicates.