Radio frequency refers to electromagnetic waves oscillating between 3 kHz and 300 GHz, the portion of the spectrum used for all wireless communication. These waves are fundamentally the same phenomenon as visible light, infrared heat, and X-rays, differing only in frequency. RF waves travel at the speed of light and can carry information by modulating their amplitude, frequency, or phase. Every wireless technology you use daily, from cellular networks and WiFi to Bluetooth and GPS, relies on RF energy propagating through free space to deliver data without physical wires.