• Electronic component that is solid-state
  • Derived from Mechanical Relay which is Electromechanical, then followed by vacuum tube which is Electronic

2 main functions

  1. Switch circuit on & off automatically with a much smaller current
  2. Amplify Signals



  • A mechanical device which is electrically operated
  • Move much slower compared to Electronic, because we are moving a physical piece that has billion times the mass compared to Electronic
  • Less durable than Electronic


  • A component which is controlled by electric current aka a stream of electrons
  • Move much faster compared to Electromechanical, because we are only moving a very small amount of electrons
  • Much more durable than Electromechanical, because we are talking about atomic level, no moving parts on a physical level