EPOC

EPOC is the general name of a family of operating systems for personal digital assistants (PDAs), produced first by Psion and now developed by a spin-off, Symbian. The name EPOC, claimed to stand for Electronic Piece Of Cheese, is deprecated, and the name Symbian OS is preferred.

EPOC seems to be the most popular PDA operating system in Europe, mainly for its good abilities to handle mobile communication.