The Fender Jazzmaster is an electric guitar that was first introduced at the 1958 NAMM Show and was designed as a more higher end model than the Fender Stratocaster, which was originally made replace the Telecaster model. As its name suggests, it was initially marketed to jazz guitarists but was more popular amoung surf rock guitarists in the early 1960s and, more recently in the 90's and beyond, by indie rock musicians.
Notable fact: Although sometimes written, Kurt Cobain never used a Jazzmaster.