In electronics, noise is a random fluctuation in an electrical signal. This happens in all electronic circuits. Noise made by electronic devices varies greatly. In communication systems, noise is an error or random disturbance of useful information in a communication channel.
The noise is the total of unwanted or disturbing energy from natural and sometimes man-made sources. Noise is usually distinguished from interference, such as deliberate jamming or other unwanted electromagnetic interference.
If a message is transmitted in a natural language (a series of letters which make sense), then it is more resistant to noise than a spoken language.
- Motchenbacher C.D. & Connelly J.A. (1993). Low-noise electronic system design. Wiley Interscience.