Saturn's largest moon is Titan.  Titan is about
40% the diameter of earth. Saturn has 20 moons,
all named after the Titans.  
In Greek mythology, the Titans were the children and the grandchildren
of the god Uranus and Gaea, the goddess of Earth.

Their names are:

Pan             Atlas           Prometheus      Pandora
Epimetheus      Janus           Mimas           Enceladus (frozen water)
Telesto         Calypso         Dione           Helene
Rhea            Tethys          Titan           Hyperion
Iapetus         Phoebe