Black noise is an informal term used to describe the absence of noise or mostly silence with bits of random noise. Unlike white noise, which contains all frequencies, black noise is the absence of frequencies and sounds. It is not a scientifically recognized term and is not a type of noise that can be measured or produced. The term "black noise" has been used in various contexts, including music and literature. For example, David Bowie and William S. Burroughs referred to "black noise" as a frequency that could crack a city or people, and described it as a new controlled bomb or noise bomb. However, this usage of the term is not related to any scientific definition of noise.