Low frequency refers to sound waves or electromagnetic waves that oscillate at a lower rate, typically below 300 Hz for sound. These low-frequency sounds are often felt more than heard, creating vibrations that can be experienced in environments like concerts or near heavy machinery. In the context of radio waves, low-frequency signals are used for long-distance communication, as they can travel further and penetrate obstacles better than higher frequencies. Examples include AM radio broadcasts, which operate in the low-frequency range, allowing them to reach listeners over vast distances.