WHAT IS A NANOMETER (nm) ?

Human red globule : diameter 8µm = 8'000nm !

meter (m)

The meter (abbreviation, m; the British spelling is metre) is the International System of Units (SI) unit of displacement or length. One meter is the distance traveled by a ray of electromagnetic (EM) energy through a vacuum in 1/299,792,458 (3.33564095 x 10-9) of a second. The meter was originally defined as one ten-millionth (0.0000001 or 10-7) of the distance, as measured over the earth's surface in a great circle passing through Paris, France, from the geographic north pole to the equator.

micron or micrometer (µm)

The micron, officially obsolete as a term of measurement, is sometimes used by microchip and wiring manufacturers in place of micrometer, one-millionth of a meter. The micron or micrometer can also be expressed as:

• - 10-6 meter
  - One thousandth of a millimeter
  - One 25-thousandth of an inch

The micron or micrometer is a unit of measure for the core in optical fiber, for which the most common diameter is 62.5 micrometers. It is also used to measure the line width on a microchip. Microprocessors are built using 0.18 or 0.13 micrometer line widths.

A human hair is said to be about 50 micrometers wide.

nanometer (nm)

Basically, it's one meter divided in one billion (1m = 1'000'000'000nm)!

Or if you prefer, one micron divided in thousand (1µm = 1'000nm)!

Think of a humain hair divided in 50'000 part along the diameter ... That's a nanometer ...