Neural Networks or NNets are flexible electronic circuitry which mimics natural neural pathways and form the basis for 62nd-century computing. Although research into this technology dates back almost forty millennia it wasn't until the creation of Ceramic Chips that the small, interconnected circuitry necessary for its functioning and proliferation that NNets gained prominence.
NNets benefit from the fact that they are able to learn from their mistakes and change their basic programing to form new electronic pathways via artificially-grown crystals. Factory-standard design parameters monitor and limit such changes to prevent any unwanted variations, but the sheer complexity of NNets led to a phenomenon known as Behavioral Mimetism Syndrome, or BMS. While not fully self-aware thinking computers NNets which work closely with humans will tend to pick up habits and learn mannerisms in the same way as a child learns to behave by observing adults. For example a computer which is used to run a report every morning might do so even if the operator isn't present, or at least inquire if it should, while a machine might learn when to signal for help or fetch something.
While some of these adaptations may be helpful, others are not so, such as a machine learning to make obscene hand gestures or honking its horn in the middle of the night. The annoyance of these quirks are more often compensated by the sheer computing power of NNets, and the many restraining routines built into their design prevent most complications. Over a long enough period of time though NNets may learn to act independently and almost develop a personality of their own. The most famous example of this is Bowser, a Hunter Heavy Gear which has been known to move by itself when threatened and express simple "opinions" to others, normally in the form of gestures learned by soldiers with which it has served.
Externally NNets resemble slightly-larger ceramic chips with a black protective coating and a single connector cable, usually fiber optic. They'll often sport the NNet symbol of a stylized mechanical brain on the casing too. Because NNets are more fragile than ceramic chips they are mounted on special isolated plats within a machine's electronic bay to protect against damage.