I.

Introduction

Electronics, field of engineering and applied physics dealing with the design and application of devices, usually electronic circuits, the operation of which depends on the flow of electrons for the generation, transmission, reception, and storage of information. The information can consist, for example, of voice or music (audio signals) in a radio receiver, a picture on a television screen, or numbers and other data in a computer.

Electronic circuits provide different functions to process this information, either in analogue or digital form. Analogue functions include amplification of weak signals to a usable level; generation of radio waves; extraction of information, such as the recovery of an audio signal from a radio wave (demodulation); and control, such as the superimposition of an audio signal on to radio waves (modulation). Digital functions include the coding, storage, and transmission of information-bearing signals in binary form, and the logic operations and numerical processing performed in computers.