First encountered by The First Doctor on their Home Planet Skaro back in 1963, the Daleks looked entirely robotic but they were in fact cyborgs, with a living body encased in and supported by an armed and mobile outer shell of Dalekanium and polycarbide protective metal armour. These were Mark III travel machines designed to carry their mutant forms, so they were not true integrated biomechanoids. In this respect, they were somewhat similar to a Cyberman; unlike them, however, the Daleks' bodies had mutated so drastically from their Kaled ancestors they had lost all humanoid appearance, save for one eye. The Daleks transmitted information using a sort of artificial telepathic network known as the Pathweb.
Daleks are an antagonist, aggressive species, and utterly xenophobic. They are noted to shout their prime goal for all non-Dalek life, "Exterminate!". Their creator Davros was first encountered by the The Fourth Doctor.