Radio waves have a very broad range of frequencies and wavelengths, which contributes to their broad range of applications. Their frequencies range from 3 kHz to 300,000 MHz, and their wavelengths range from .3 m to 90 m.
Artificial sources produce many of the radio waves that serve beneficial purposes in our everyday lives. The two types of these waves are digital and analogue. Both see use in different areas of our lives; analogue waves are more frequently used in radio, whereas digital waves are used television programming. However, radio waves can also originate from astronomical objects such as Jupiter, our sun, and the center of the milky way galaxy.
Beyond entertainment, there are several useful applications of radio waves. Radio waves, when concentrated in a specific area, can greatly heat that area. This can be used for minimally invasive surgeries, such as a cardiac surgery where a diseased area of the heart is destroyed through concentrated application of radio waves. Refraction of radio waves can also be used to image objects through walls by analyzing the varying speeds at which they travel through different mediums. This would allow law enforcement to see what was inside a building in, for example, a hostage situation.
There are no safety precautions necessary when dealing with radio waves, as it is nearly impossible to accidentally injure oneself with them.