Ogrons are low-intelligence, ape-like hominids who live in scattered communities on an unnamed planet on the outer fringes of the Milky Way, far from the central spaceways. The dominant lifeform on their home planet is a giant slug-like lizard named the Eater, and the Ogrons both pray to and are preyed on by it.
Ogrons are hired mercenaries. Those who have employed their services include the Daleks and the Master when he was working for the Daleks. On some human planets, Ogrons are employed as police officers, usually led by a mentally augmented leader.
Davros was originally the head of the Kaled Scientific Elite, on the planet Skaro, but became better known as the creator of the Daleks. During the Imperial-Renegade Dalek Civil War, he served as Emperor of the Imperial Dalek faction and later of the Dalek race as a whole, but his relationship with his creations was always tense. He was frequently hunted, maligned or otherwise denigrated by some portion of the overall Dalek population.
Despite the fact that he was not the unquestioned ruler of the Daleks, he was one of the Doctor's greatest enemies, rivalling the Master in intellect and madness. Because of his creations, he was responsible for trillions of deaths and war across the universe.
The Daleks used suicide bombers to destroy a Movellan ship.
During the 22nd century Dalek invasion of Earth the Daleks used these surgically modified captives for patrols and overseeing other slaves. The robomen were needed because there were few Daleks on Earth.