Radio waves are electromagnetic waves with a frequency of about 3 kHz to 300 GHz. Microwaves are a subset of the radio waves with frequencies ranging between 300 MHz and 3 GHz.
Radio waves are generated by the movement of electric charges on the antenna, and referred to as radio frequency (RF) radiation, for irradiating the area away from the source, i.e. the transmitting antenna.
The airwaves belong to the category of non-ionizing radiation as it is unable to break chemical bonds or to extract electrons from atoms, causing ionization of matter such as radiation (X-rays, gamma rays). In contrast to ionization, which is dangerous because it can lead to deterioration of the genetic material and cause harmful effects on health (such as cancer), the main biological effect of radio waves under certain circumstances is the increase of tissue temperature exposed to them. To date studies have not documented a causal relationship between this type of radiation and its harmful effects on health.
It is important to distinguish between ionizing and non-ionizing radiation for only then perceived material risks possibly caused by electromagnetic radiation.
check out more info about radio waves at Khan Academy Dep. of Physics.