A Dalek is a fictional alien creature in the British science-fiction series Doctor Who, that first appeared on BBC television in 1963. The Daleks were created by Terry Nation, who based them on the Nazis, and were designed by Raymond Cusick. Today, the word 'Dalek' has entered British English to denote someone or something with fascistic views or extremist behaviour.
The Daleks are usually thought of as metallic creatures with no human features, best-known for screaming "Exterminate!!" at anything un-Dalek: their motive, founded on racial purity and hatred of anything that is not Dalek, is to destroy all other life in the universe. In this objective they have been thwarted many times by a traveller in time and space known as 'the Doctor'. Most Daleks are armed with an exterminating gun and an appendage which looks not unlike a sink plunger (because this was all the BBC could afford at the time), and their tops rotate 360 degrees to allow them to see in any direction through a special eyestalk. Inside each Dalek casing lies the mutated remains of a creature which is completely dependent on the metal outer shell for life support. The Daleks originated on Skaro, a world once home to their ancestors, the Kaleds (or Dals), as well as the Thals. A Kaled scientist known as Davros created the Daleks as a weapon by mutating Kaleds into a horrific mutant form, while the Thals remained humanoid. The war between the Daleks and their many enemies depicted in several Doctor Who serials from the 1960s to the 1980s, and they have also appeared in the latest series of the programme, where it has been revealed that they were mostly destroyed along with the Doctor's own people, the Time Lords, in a final great battle known as the 'Time War'.
In real life, each Dalek prop is controlled by a human operator inside, with an actor providing the voice via a microphone. Lights atop the main dome were intended to flash in time with the creature's speech, but in reality were included so that actors could tell which Dalek was supposed to be addressing them. The dome was originally moved by the operator and, in the 21st century, by radio control, leaving the operator free to concentrate on the other appendages. The image of the Daleks led to the so-called 'Dalekmania' craze of the mid-1960s in the UK, around the time two big-screen remakes of televised Doctor Who Dalek stories were released. The Daleks appeared regularly throughout the 1960s in the television series, but aside from one Doctor-less stage play and a handful of audio plays many years later, the Daleks have rarely won success outside Doctor Who itself.
The Daleks' creation generated a series of popular myths regarding how Nation came up with them. These included the fictitious claim that their name came from the spines of series of dictionaries, and the idea that he had based their design on a pepperpot. In fact, Nation had provided a very general description of the creatures in his script, e.g. specifying that they should have no human features and appear to glide along the floor, but it was left to BBC designer Raymond Cusick to come up with the memorable final design, which was not based on pepperpots at all, but had started from the idea of a human operator sitting on a chair. Cusick received an ex gratia payment for his work, while Nation retained the rights and therefore received an income from their appearances.