  A simple methodical derivation for Landauer quantization of the conductivity
is derived as a simple consequence of the Bohr quantization laws. The level of
explanation corresponds to high-school level of Physics education and can be
used as popular lecture for students. The purpose of the work is to introduce
students in an achievement of nano-technology which is relevant to the future
electronics. Using only the fundamental laws of quantization students can
understand a contemporary experimental research and to follow future
development in the field.
