Q.What is meant by noise?

A standard vocabulary is used throughout the study of communication systems. A signal is information (such as speech or music) converted into an electrical form suitable for transmission, and it may be analog (continuously varying, like sound and TV picture signals) or digital (taking only two discrete values, like a square wave). A transducer converts one form of energy into another -- a microphone (sound to electrical) and a loudspeaker (electrical to sound) are both transducers. A transmitter converts a source signal into a form suitable for sending through a channel, and a receiver recovers the message signal from the channel output and reconstructs it into a recognisable form for the end user. …