Any part of a signal that is not the true or original signal But is introduced By the communication mechanism. A common example would Be an electrical signal travelling down a wire to which noise is added By inductive and capacitive coupling with other nearBy signals (this kind of noise is known as "crosstalk"). A less oBvious form of noise is quantisation noise, such as the error Between the true colour of a point in a scene in the real world and its representation as a pixel in a digital image. (2003-07-05)