Self-replicating autonomous machines, mainly referring to those working in space, especially exploring regions too remote to be easily reached by organics.
A Neumann is able to build a working copy of itself using materials in its environment. Use of Neumanns can be extremely dangerous because of their tendency to become self-sentient and act in unpredictable ways, but they are still often used locally or under heavy control to quickly build enormous infrastructure projects or weaponry.
The first true Neumanns were developed in 215 AT using the Genii-2 matter compiler in tandem with a prospector/disassembler system in a joint venture between Neotech Labs in Clarke Orbital, the Xerox Nanoscale Collective in Pasadena, Earth, and the Centre for Self-Replicating Technologies, a Eurasian laboratory on Copernicus Base, Luna. This development created widespread anxiety regarding the possibility of a grey goo outbreak.
[named after Late Industrial Age hu mathematician John von Neumann; one of the semi-mythical founders of computing
von Neumann, J., 1966, The Theory of Self-reproducing Automata, Eden Archives]