Dalek

The Daleks are a made-up alien race of mutants from the British science fiction television series Doctor Who. Daleks are aliens from the planet Skaro, integrated within a tank-like metal casing. The creatures are a powerful race who always wanted universal conquest and control, they have no pity, feelings or guilt (as all of their emotions were removed except hate).
The Daleks are one of the most powerful races ever in Doctor Who history and are the Doctor's worst enemies. They cry "EX-TER-MIN-ATE!" when they are about to kill someone. They come in different colours, like bronze, black, red, white, gold, and silver. They first appeared in the first season episode of the series (in "The Daleks") and they were last seen in the Series 7 episode "Asylum of the Daleks" (2012). They are not robots, but horrible aliens kept in a metal casing, because they became mutated during a war on their planet, Skaro. They were created by an evil scientist named Davros. They can not be easily hurt by guns as their casing reflects the bullets that come from the gun and a shield melts bullets shot at them.
Daleks were created by writer Terry Nation and designed by BBC designer Raymond Cusick. They were introduced in December 1963 in the second Doctor Who serial. From their first appearance they became very popular with viewers. They appeared in many later serials and two 1960s motion pictures.
The word "Dalek" has been put into the Oxford English Dictionary and other major dictionaries; the Collins Dictionary defines it rather broadly as "any of a set of fictional robot-like creations that are aggressive, mobile, and produce rasping staccato speech". Although there is no meaning to their name, "Dalek" sounds like the Norwegian word "darlig", which means "bad" or "evil". It is also a trademark, having first been registered by the BBC in 1964 to protect its range of Dalek merchandise.
The Daleks were on a postage stamp celebrating British popular culture in 1999, photographed by Lord Snowdon.
Physical characteristics
On the outside, Daleks resemble human-sized salt and pepper shakers who are five to six feet (152 to 183 cm) tall. On the top, they have a rotating dome with a telescope for seeing. They have two arms. One arm has an energy weapon (or "death ray"), which looks like an long egg beater or the framework of a paint roller. In some episodes, this could also fire a gas or projectiles. Their other arm is a telescope with a plunger on the end, which they use as a hand. The actual Dalek creature inside the metal casing is very rarely seen. It looks like an octopus or a squid.
Movement
Early versions of the Daleks were rolled around on castors or moved by wheels connected to hand cranks by bicycle chains.
Later versions of the prop had more efficient wheels (from shopping carts, according to a Blue Peter episode) and were simply moved by the seated operators' feet, but they remained so heavy that when going up ramps they often had to be pushed by stagehands out of where the camera could not see. The difficulty of operating all the prop's parts at once contributed to the occasionally jerky movements of the Dalek. The latest model of the costume still has a human operator within, but the movement of the dome and eyestalk are now remotely controlled so that the operator can concentrate on the smooth movement of the Dalek and its arms.
Fictional history
The Daleks have appeared on the show many times and their design has seen many changes. This means that it can be difficult to make sure that the storylines line up. When the Daleks first appeared in The Daleks, they were presented as the descendants of the Dals, mutated after a brief nuclear war between the Dal and Thal races. However, in 1975, Terry Nation revised the Daleks' origins in Genesis of the Daleks, where the Dals were now called Kaleds (of which Daleks is an anagram), and the Dalek design was attributed to one man, the crippled Kaled chief scientist Davros.
Instead of a short nuclear exchange, the Kaled-Thal war was portrayed as a thousand-year-long war, fought with nuclear and other weapons causing widespread mutations among the Kaled race. Davros experimented on living Kaled cells to find the ultimate mutated form of the Kaled species and placed the subjects in "travel machines" whose design was based on his own life-support chair.
Genesis of the Daleks marked a new era for the depiction of the species, with most of their previous history either forgotten or barely talked about again.
A single Dalek appeared in "Dalek", written by Robert Shearman, which was broadcast on BBC One on 30 April 2005. This Dalek appeared to be the sole Dalek survivor of the last Time War that had destroyed both the Daleks and the Time Lords.The Doctor had guessed that this Dalek had "fallen" out of the time war.
The Dalek Emperor returned at the end of the 2005 series, having rebuilt the Dalek race with human subjects; it saw itself as a god, and the new Daleks were shown worshipping it. This terrified the Doctor as "Daleks have no concept of blasphemy." These Daleks and their fleet were erased from time itself in "The Parting of the Ways".
The 2006 series finale "Army of Ghosts"/"Doomsday" saw another squad of Dalek survivors from the old Empire, known as the Cult of Skaro, led by a black Dalek named "Dalek Sec", that had survived the Time War by escaping into the Void between dimensions. They emerged, along with a Time Lord prison containing millions of Daleks, at Canary Wharf due to the actions of the Torchwood Institute and Cybermen from a parallel world, leading to a Cyberman-Dalek clash in London. Eventually, the Tenth Doctor caused both factions to be sucked back into the Void. However, the Cult members (Sec, Caan, Jast, and Thay; it is unusual for a Dalek to have a name) survived by "temporal shifting" away. The two-part story "Daleks in Manhattan"/"Evolution of the Daleks" revealed they had escaped to 1930 New York, setting up base in the Empire State Building, which was being built at the time. Experiments led by Sec attepted to force a Dalek evolution by combining their DNA with that of humans, and he is the first of the new "Human-Daleks". However the three remaining Daleks rebelled and destroyed him because he was not a pure dalek. The Cult also attempted to create a Human/Dalek hybrid (fully human in appearance but with Dalek minds). This attempt failed after the Doctor interfered. Caan escaped via another temporal shift.
The Daleks returned in the 2008 series' two-part finale, "The Stolen Earth"/"Journey's End", accompanied once again by their creator Davros (now played by Julian Bleach). It is revealved that Dalek Caan had forced himself back into the Time War, even though it was "time-locked" or prevented from entering by any means (the effort rendered him insane), where he rescued Davros; Davros then created a new army of Daleks from his own flesh. The new Dalek army was led by a Supreme Dalek, who kept Davros imprisoned in a "Vault"; Davros said that he and the Supreme Dalek had reached "an arrangement". Davros and the Daleks planned to destroy all creation with a 'reality bomb', which failed due to the interference of the Doctor and his companions, and due to Caan himself who had been manipulating the events unknown to either side. Though the Daleks were destroyed, the fate of Davros and Dalek Caan is unknown. 3 Daleks from this episode came back in Series 5 (Victory of the Daleks). They created 5 new, different colored daleks. These new Daleks escaped into space. Later, they showed up in "The Pandorica Opens" and trapped the Doctor in the Pandorica, the ultimate prison. After they were erased from time by the cracks, a stone Dalek showed up, which was an echo of the Dalek race. It was brought alive by the Pandorica light, which could restore thing which had been erased by the cracks. It was later shot in the eye by River Song. Their race, along with the rest of the universe, was brought back by the Doctor.