2.45 GHz Microwave oven and Wi-Fi I noticed that both microwave oven and Wi-Fi use the same frequency band 2.4-2.5 GHz. Yet microwave oven will certainly fry a living being the Wi-Fi has not done yet I suppose. 
So why is Wi-Fi harmless and microwave oven harmful to us? 
Why won't our bodies absorb the Wi-Fi energy through dielectric heating like it does if put in a microwave oven? 
 A: Our bodies do absorb Wi-Fi energy, which causes the signal to attenuate. The thing is that the signal is so weak compared to a microwave oven that our bodies are able to get rid of the extra energy as fast as we accumulate it. Your skin just isn't going to heat up measurably.
If you stand to close to a radar transmitter, for example, you will experience some discomfort (apparently this is how the idea of microwave ovens came about)
A: First of all, the Wi-Fi doesn't have a defrost setting, we have that going for us. Jokes aside, I looked at the microwave and Wi-Fi that I have, and the first major difference is the power level. The microwave outputs $400W$ to $2kW$ where the for the Wi-Fi is just around $5W$. Also, the microwave runs on a single frequency in a very confined and shielded space. So all that power is focused in a small region of space. Where as for the Wi-Fi, all that energy is radiated "symmetrically". So your body will receive only a small fraction of its output. But if you where to surround yourself with hundreds of Wi-Fi's my guess is that you'll start to feel some discomfort.      
