Casio Cassiopeia was the brand name of a PDA manufactured by Casio. It used Windows CE as the Operating system. Casio was one of the first manufacturers of PDAs, developing at the beginning small pocket-sized computers with keyboards and grayscale displays and subsequently moving to smaller units in response to customer demand.
Read more about Casio Cassiopeia: Cassiopeia A-10 and A-11, Cassiopeia A-20, Cassiopeia E-10, Cassiopeia E-11, Cassiopeia E-15, Cassiopeia E-100, Cassiopeia E-105, Cassiopeia E-115, Cassiopeia E-125, Cassiopeia E-200, Successors of The Cassiopeia E-200, Other Models