Electronics is the science of how to control electric energy, energy in which the electrons have a fundamental role.Electronics deals with electrical circuits that involve active electrical compo nents such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive electrical components and interconnection technologies. An electronic component is any physical entity in an electronic system u sed to affect the electrons or their ,associated fields in a manner consistent with the intended fun ction of the electronic system. Components are generally intended to be connected together, usually by being solde red to a printed circuit board (PCB), to create an electronic ,circuit with a particular function (for example an a mplifier, radio receiver, or oscillator).