In the world technology and science it is often an unwanted phenomenon. Noise is present in all analog devices, but the digital domain is principally noise free. In digital world there are only combinations of zero and one, everything else is considered as an error.
Humans are accustomed to process information which contains noise and errors.
The current digital systems can often appear too sterile to the human senses. There are different kind of noises. The most important characteristic of noise is that it is always unpredictable. Real, natural noise cannot be fully predicted, but it can be simulated with various mathematical formulas. The human generated arts, such as music, contain patterns and elements which have interesting relation to noise.