There are a number of races in the universe of the Imperium of the Terran Throne. None of these races are genuinely extraterrestrial. The dominant race is homo sapiens sapiens (humanity). Some humans are still nautrally born, but the majority are artificially produced by cloning.
There are also various races of intelligent, animal-human hybrids who are always produced by cloning and are derived from both human D.N.A. and those of Earth animals. There are a race of Centaurs, cloned with both human and horse genes, are look and act like their namesakes from ancient Greek mythology. There are also a race of Primate-Canines, cloned from chimpanzee, gorilla, human, and dog D.N.A. Then there are Centans, who are cloned with human, dolphin, and porpoise genes, and they are naturally mobile in water or in zero gravity, though more sluggish when moving on solid land and/or in Earth-like gravity. There are Bat-Avoids, produced from human, bird, and bat D.N.A., and are physically weak but capable of natural flight. The four aforementioned species are by far the dominant races of chimeras.
Finally, there are plenty of robots and computers, many (but not all) of whom have personalities with A.I. (artificial intelligence).
See also Technology in ITT universe.