It is a hypothetical future level of technological manipulation of matter, on the scale of trillionths of a metre or picoscale (10−12).
A further hypothetical development, femtotechnology, would involve working with matter at the subatomic level.
Picoscience is a term used by some futurists to refer to structuring of matter on a true picometre scale.
Alternatively, picotechnology is used by some researchers in nanotechnology to refer to the fabrication of structures where atoms and devices are positioned with sub-nanometre accuracy.
The Chinese science fiction novel The Three-Body Problem features a plot-point in which an advanced alien civilization imbues individual protons with supercomputing powers and subsequently manipulates said protons via quantum entanglement (the fictional name for these proton-sized supercomputers is "sophons").