Micro(system) technology is technology that focuses on products and processes at submillimetre, micrometre scale. Formally speaking, this definition includes microelectronics, but in view of the huge scope and early development of that domain, the term micro(system) technology is usually used in the main for products and processes relating to movements on the micro scale other than electronic ones. In particular, it pertains to electromechanical movement, MEMS, fluid currents, lab-on-a-chip and microfluidics, light, light-on-a-chip, photonics and living organisms, biochips.
Nanotechnology is technology concerned with particles measuring nanometres (a billionth of a metre). In terms of size, this is a scale just above that of atoms (0.060 nm to 0.275 nm) and simple molecules. A criterion is that a structure in at least one dimension must not exceed 100 nanometres in size. Nanotechnology distinguishes itself from nanoscience in the sense that nanotechnology is focussed on working with small particles and that nanoscience allows itself to be defined as all science engaged in research at the nano scale.