SYMBIAN OS

Symbian OS is a operating system for mobile devices. It associated with libraries, framework and some common tools. Symbian OS is developed by Symbian Ltd. Symbian Ltd was partnership With Nokia, Ericsson, Motorola and Psion.

Symbian OS, with its roots in Psion Software's EPOC, features Pre-emptive multitasking and memory protection , like other operating systems (like computers). EPOC's approach to multitasking was inspired by VMS is based on asynchronous server-based events.

Structure of Symbian

symbian model contains:

• UI Framework Layer
• Application Services Layer
  • Java ME
• OS Services Layer
  • generic OS services
  • communications services
  • multimedia and graphics services
  • connectivity services
• Base Services Layer
• Kernel Services & Hardware Interface Layer

Psion

Psion was found by David pottar


EPOC

Electronic Piece Of Cheese