Ace Frehley. Joe Walsh. Eric Clapton. Three electric guitarists. Their sound depends not so much on wood as it does on bar magnets and copper coils. We are talking about guitar pickups, the component that makes the guitar electric.

The first electric instruments began appearing in the 1920's. Early electric guitars were acoustic instruments with a contact microphone mounted on the guitar's body. While this gave a guitarist the volume needed to be heard over a big band, it also amplified any noises made by striking the instrument and sometimes nearby conversations.