A cyborg is a sentient being with mechanical/electrical enhancements. For the OAGS rules for Cybenetic Augmentations circa 2059 see this article

In the Theta Wars mechanical enhancements to the human body are fairly common, but they have been in existence as early as the early 20th century in the form of things such as pacemakers. Of course, in the Theta Wars, they are much more sophisticated and can cater to a wider range of afflictions, and indeed some voluntarily undergo surgery to add cybernetics to give themselves enhanced properties. This was thought of as taboo for the longest time.

A cyborg is always a sentient being, ie a sentient xenoform or a human, that has undergone cybernetic surgery in order to enhance themselves, be it voluntarily or otherwise. People taking cybernetic upgrades that merely aid a deficiency, such as a normal bionic limb to replace a lost one or bionic eyes to cure blindness are not considered cyborgs unless that the enhancement is a considerable upgrade to their normal limits, or they take additional enhancements.

Cybernetics are a human invention developed in the prime universe without xenoform intervention. The first pair of working bionic eyes were developed in Japan in 2044 as a cure for blindness and a revolution in medicine. Since then, Japan has led the world in bionic research, and Japanese military and secret forces are always equipped with the most sophisticated bionics in the world. Agents from the Hiroshima Aruki Chrono Soldiers (HACS) are regularly outfitted with wild pink filters, the most advanced piece of human technology known.

Outside of Japan, cybernetics are routinely used, however the Alpha Machine makes thorough use of them. They have a unique and secret form of bionics which actually replace lobes of the brain which only Japanese secret services are aware of. These bionic brains as you can imagine combine human brain function with the incredible power of advanced computers. All members of Alpha Machine can communicate by 'thinking' to each other with no interference from psychics, can connect to both local and global networks, and can surrender the use of their bodies to others with similar bionics in order to utilise their skills and knowledge on the other side of the planet.

Xenoforms also use bionics, though in the time of the theta wars it is still a young technology in their worlds. Bionic limbs and eyes are relatively simple procedures, as they are merely a case of connecting electronic receivers to nerves and muscle. Bionic organs too dissimilar to human organs tend to be much rarer in the more radically different xenoforms. For example, plant based xenoforms don't have any cybernetics related to photosynthesis as humans have no similar organ.