Radio is the radiation (wireless transmission) of electromagnetic signals through the atmosphere or free space from one device to another. Information, such as sound, is carried by systematically changing (modulating) some property of the radiated waves, such as their amplitude, frequency, phase, or pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form. This is simply how sound is carried through the airwaves and we are able to make out the sounds. And communicate with one another wirelessly.