This is a textbook for students tackling analogue electronics, that is tailored to BEng and HNC/D electronics courses. The basic theorems and laws are presented in a first chapter of revision, and subsequent chapters cover biasing, load lines, transistor modelling, current gain, voltage gain, cascaded systems, Bode plots, capacitors, high frequency, op-amps and bandwidth gain, showing how circuits work, and how circuits can be represented by equations.