What electromagnetic waves are used for communication?
Microwaves and radio waves.
According to BBC :
"Microwaves and radio waves are used to communicate with satellites. Microwaves pass straight through the atmosphere and are suitable for communicating with distant geostationary satellites, while radio waves are suitable for communicating with satellites in low orbit."
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The main reason why we use radio waves and microwaves probably have to do with the fact that they are low in energy, due to their long wavelengths and low frequency- and therefore have a low ionizing ability on other materials. This makes them rather safe for commerical and non-commerical use alike.