Short answers, pulled from the story.
George Beauchamp and Adolph Rickenbacker created the first commercially marketed electric guitar in 1932. They called this instrument the Frying Pan because its cast aluminum body resembled a small skillet.
Gage Brewer performed the first publicly promoted electric guitar concert in Wichita, Kansas during October 1932. His performance demonstrated how an amplified string could cut through the volume of a full orchestra.
Leo Fender produced the first mass-produced solid-body guitars known as the Esquire and Broadcaster in 1950. These instruments arrived five years after Les Paul created his original prototype.
Alder produces a brighter sound while swamp ash offers more pronounced highs and lows. Mahogany provides dark bassy warmth and poplar resembles alder tonally.
Floyd Rose introduced locking nuts and bridges in the late 1970s to prevent guitars from losing tuning under heavy vibrato bar use. Early vibrato systems often proved unreliable and caused guitars to go out of tune easily.