Z80 CP/M Emulator is running the Baffa-2 Computer ROM and started with CP/M 2.2 Operating System.

If you need more information about CP/M there is an excelent article at wikipedia that tells a little about its history and how it works.

Drive B: has Microsoft Basic (MBASIC.COM) and many Basic Laguage programs. To exit from MBasic type SYSTEM.