This guitar is about ten microns (10 x 10^-6 m) long, about the size of a red blood cell. For comparison, the thickness of a human hair is about 200 microns, 20 times the length of this guitar. The "strings", actually rods of silicon, are only 50 nanometers wide or about 100 atoms across.

What is a nanometer?
The table below lists some objects, with a characteristic length dimension for each, rounded to the nearest power of ten.

Note that objects that can be seen in an optical microscope, like the human hair and red blood cell, are larger than the wavelength of light.