A cyborg is a cybernetic organism (i.e. an organism that is a self-regulating integration of artificial and natural systems). The term was coined in 1960 when Manfred Clynes and Nathan Kline used it in an article about the advantages of self-regulating human-machine systems in outer space. D. S. Halacy's Cyborg: Evolution of the Superman in 1965 featured an introduction by Manfred Clynes, who wrote of a "new frontier" that was "not merely space, but more profoundly the relationship between 'inner space' to 'outer space' -a bridge...between mind and matter." The cyborg is often seen today merely as an organism that has enhanced abilities due to technology, but this perhaps oversimplifies the category of feedback.
Fictional cyborgs are portrayed as a synthesis of organic and synthetic parts, and frequently pose the question of difference between human and machine as one concerned with morality, free will, and empathy. Fictional cyborgs may be represented as visibly mechanical (e.g. the Borg in the Star Trek franchise); or as almost indistinguishable from humans (e.g. the Cylons from the re-imagining of Battlestar Galactica). These fictional portrayals often register our society's discomfort with its seemingly increasing reliance upon technology, particularly when used for war, and when used in ways that seem to threaten free will. Real cyborgs are more frequently people who use cybernetic technology to repair or overcome the physical and mental constraints of their bodies. While cyborgs are commonly thought of as mammals, they can be any kind of organism.