Lester William Polsfuss (June 9, 1915 – August 12, 2009)—known as Les Paul—was an American jazz and country guitarist, songwriter and inventor. He was a pioneer in the development of the solid-body electric guitar which “made the sound of rock and roll possible”. He is credited with many recording innovations. Although he was not the first to use the technique, his early experiments with overdubbing (also known as sound on sound), delay effects such as tape delay, phasing effects and multitrack recording were among the first to attract widespread attention.
For the whole story, checkout wikipedia http://en.wikipedia.org/wiki/Les_Paul