Types of radio waves

of light
transferred through space energy emitted from an electromagnetic oscillation generator
born at the change of the electric field
characterized by frequency, wavelength and power portable energy

For space communications
For sea communications
Transmission data and medicine
For radiolocation and radionavigation

the transmission of long-wave broadcasting stations can be taken at a distance of several thousand kilometers
medium wave stations are audible within a thousand kilometers.
The energy of the short waves dramatically decreases as the distance from the transmitter.
study of short and ultrashort waves showed that they quickly disappear when you go near the Ground. When the direction radiation upward short wave back

the atmosphere.  on the propagation of waves shorter than 1 cm are affected by fog, rain, clouds, strongly limiting the communication range.