A notch filter is a type of electronic filter designed to remove a specific frequency from a signal while allowing other frequencies to pass through. This is useful in various applications, such as audio processing, where unwanted noise or interference at a particular frequency needs to be eliminated. Notch filters are commonly used in telecommunications and music production to improve sound quality. They can be implemented in both analog and digital formats, with digital notch filters often found in software used for audio editing. By targeting and attenuating a narrow band of frequencies, notch filters help enhance the overall clarity of the desired signal.