This book relates the recent developments in several key electrical engineering R&D labs, concentrating on power electronics switches and their use. The first sections deal with key power electronics technologies, MOSFETs and IGBTs, including series and parallel associations. The next section examines silicon carbide and its potentiality for power electronics applications and its present limitations. Then, a dedicated section presents the capacitors, key passive components in power electronics, followed by a modelling method allowing the stray inductances computation, necessary for the precise simulation of switching waveforms.