As the name implies, nanoscopic robots are semi-autonomous machines with sizes on the order of magnitude of billionths of a metre. Individually, these tiny machines are insignificant, but working in large numbers they have some extraordinary capabilities. They can manipulate and assemble matter on a molecular level, and were originally created as a means of manufacturing anything (potential cornucopia machines). However, this proved to be impractical for most general purposes, as truly unlimited manufacturing capability is actually harder and more expensive to accomplish than almost anything that you might hope to manufacture from it. Nevertheless, specialized variants of nanoscopic robots are exceedingly useful and popular.
By far the most common use of nanoscopic robots is as an augmentation for biological beings. They drastically bolster the immune systems, accelerate healing, boost oxygenation and other general physiological tasks, and even counteract the effects of aging. A great many aesthetic aspects of physiology actually become mutable with the nanoscopic robots. Also, with some additional programming they can be used to construct additional minor features or internal technology.
In modern AIF, it is essentially unheard of for any being to be without an army of nanoscopic robots distributed throughout their entire body. They are transmitted from mother to child in general reproduction, and they are the usual medium for building beings without mothers. They are self-replicating, making themselves from the same material as the being they reside in, plus making use of whatever additional trace elements might occasionally be introduced into the body. Historically, during the time of the Confederation - when nanoscopic medical robots were developed, species were enticed into joining the Confederation largely in part because having their populations make use of the technology.
Describing the abilities of nanoscopic robots in terms of game mechanics, they permit a being to heal at a basic and unassisted rate of 1 point per standard day - as compared to 1 point per week for un-augmented beings. Nanoscopic robots are also required for making full use of modern AIF medical gear; without the helpful resident nanoscopic robots and their familiarity with the host genome, proteome, and phenotype, all dice are reduced to being just one point each. Meaning that a 1 die med kit will only be able to heal 1 point per hour, and a second stage medic with a +2 dice bonus to heal will only be able to heal an additional 2 points - when there are no nanoscopic robots present in a subject being. For role-playing description, the nanoscopic robots turn virtually every being into Olympic-class athletes in terms of endurance, or even better, and can keep every aspect of health optimal (excepting, of course, damage inflicted from combat). Using public-domain programs, the nanoscopic robots are usually also configured to create technological artifacts inside beings - the most common of these being basic communicators, sensors, computers, and grip pads. Additionally, virtually all control mechanisms are designed to interface via the nanoscopic robots, which allow for a direct neural connection. This applies to controls for starships, operating coffee machines, and pretty much everything in-between.
Due to the overwhelming success of nanoscopic robots for maintaining biological beings, mechanical entities have developed analogous robots. Robots too now generally have nanoscopic robots to assist with their repairs, and even in generation of basic equipment like the biological variants. Even ships now often have monster versions - microscopic robots - which are gigantic compared to the robots used for personnel.