Positional assembly is a technique that has been suggested as a means to build objects, devices, and systems on a molecular scale using automated processes in which the components that carry out the construction process would follow programmed paths. "From" molecules would be positioned by computer control to form the "to" molecules that would compose the object, device, or system being assembled.
Positional assembly is a high-precision form of self-assembly . Self-assembly is, in turn, one of the components of molecular manufacturing , a branch of nanotechnology that involves the use of nanoscale (extremely small) tools and processes to build objects, devices, and systems at the molecular level. Nanotechnology is a field of engineering that deals with design, manufacture, and control on a scale of a few nanometer s (nm) or less, where 1 nm = 10 -9 meters.
Nanotechnology has potential benefits, including water purification, sanitation, agriculture, alternative energy (particularly photovoltaics), home and business construction, computer manufacturing, communications, and medicine.