Irving Ashby was an accomplished American jazz guitarist, known for his precise and rhythmic playing style. He played a substantial role in the 1940s and 1950s jazz scene, notably as a member of the Nat King Cole Trio from 1947 to 1951. Ashby's signature sound, characterized by elegant riffs and smooth runs, is well-reflected in the Trio's influential works like "The Christmas Song". His contribution to jazz guitar has been significant, influencing many artists and contributing to the evolution of the genre.