What are microwaves?

Question

What are microwaves, not microwave ovens? Is it radiation? Does a microwave oven have radiation in it?

Answer 1

Microwaves are electromagnetic waves with wavelengths ranging from 1 mm to 1 m, or frequencies between 300 MHz and 300 GHz.

Apparatus and techniques may be described qualitatively as "microwave" when the wavelengths of signals are roughly the same as the dimensions of the equipment, so that lumped-element circuit theory is inaccurate. As a consequence, practical microwave technique tends to move away from the discrete resistors, capacitors, and inductors used with lower frequency radio waves. Instead, distributed circuit elements and transmission-line theory are more useful methods for design, analysis. Open-wire and coaxial transmission lines give way to waveguides, and lumped-element tuned circuits are replaced by cavity resonators or resonant lines. Effects of reflection, polarization, scattering, diffraction, and atmospheric absorption usually associated with visible light are of practical significance in the study of microwave propagation. The same equations of electromagnetic theory apply at all frequencies.

Answer 2

Very high frequency radio waves.  Research is still being done on potential health effects of microwave radiation.  This is electromagnetic in nature, not like a radioactive isotope.

Answer 3

calmze said that  "(microwaves) have lower frequency than light so they're not dangerous."

calmze is dangerously confused, they can be very dangerous indeed.

Answer 4

microwaves refers to electromagnetic radiation in a particular frequency range.  they have lower frequency than light so they're not dangerous.  em radiation is not the same as nuclear bomb radiation (which are actually particles like alpha, beta, gamma).  microwave ovens actually use microwaves to cook food.  

you should take a physics class since it's impossible to cram 1 semester of physics into this response.