The Daleks are a fictional extraterrestrial race of mutants from the British science fiction television series Dr Who. The mutated remains of the Kaled people of the planet Skaro, they travel around in tank-like mechanical casings, and are a race bent on universal conquest and destruction.
They are also, collectively, the greatest alien adversaries of the Time Lord known as the Doctor, having evolved over the course of the series from a weak race to monsters capable of destroying even the Time Lords and achieving control of the universe.
As is common in long-running series whose back-stories are not mapped out and which are also the product of many different writers over the course of years, the fictional history of the Daleks has seen many retroactive changes and these have caused some continuity problems.
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