Machine people or machine humans (機械人間 kikai ningen in the original Japanese) are people who have transferred their consciousness into mechanical bodies, thereby becoming effectively immortal. This procedure is extremely expensive, and on most worlds can only be afforded by the very rich. However, the final stop at the Andromeda end of the GE999's run, Planet Promethium, will perform it at no cost to anyone who requests it.
Machine people tend to find flesh-and-blood humans to be a discomfiting reminder of their mortal origins, shading sometimes into murderous hatred as in the cases of the inhabitants of the Double Planet and "human hunters" like Count Mecha.
Meaning and Translations
The name may be a play on words, since 機械 (kikai machine) is a homophone of 毀壊 (kikai ruined or destroyed), which would fit well with the author's generally negative portrayal of the concept.
The first English-language fansubs of the TV series by Live-eviL used the translation "mechanized human". All the official subtitled versions to date translate it as "cyborg", which may cause viewers some confusion since "cyborg" usually doesn't refer to a completely mechanical being, as the machine people are sometimes implied to be. ("Cyborg" in Japanese is 人造人間 jinzou ningen.)