Make: Electronic Music from Scratch

A switch at any point is either open or closed. When a switch is off, it means the

circuit is open and no energy is flowing through that part of it. When a switch is

on, it means that part of the circuit is closed and electrons are chugging along.

There are two major categories of switches: maintained and momentary. A

maintained switch is what we normally think of as an on/off switch. It keeps the

state it is set to until someone flips it back, like when Dr. Frankenstein flips the

big, clunky lever on the wall. A momentary switch, however, springs back into its

initial position as soon as you finish actuating it—like your computer keyboard