L1, Introduction

The word electronics is derived from "electron." Electrons are sub-atomic particles with a negative charge. The unit for electric charge is the coulomb. One coulomb equals the charges of 6.24 x 1018 or 6.24 quintillion electrons. A single electron has a charge that is too small to measure in most electronic devices, so scientists use coulombs as a more useful way to describe charge,

Electron a tiny particle which forms part of all atoms, which, as everybody knows, make up everything in the world. Atoms contain other types of particles - protons and neutrons - but it is the electrons which will be interesting us here.