In 1961 the Gibson designers felt that the "old" Les Paul signature model had become boring. They decided to alter the design a bit, and ended up with what is now know as the SG. They released it under the name Les Paul, but Les Paul himself did not like this new guitar. He ordered Gibson to find a new name for it. The designers asked themselves what to call this new special guitar, and eventually ended up calling it SG (Special Guitar). This became it's new name. Gibson had already sent out some guitars on the market with a Les Paul logo on them; these are collectors items today.
Famous players of the SG include Angus Young, Pete Townshend and Jimmy Page.