This is a Z80 and CP/M emulator (with an MMU and 1MB of RAM no less)
Drive E: is mapped to userdrive1 in the appdata directory (created on first run) but will appear only if you put files in it.
To exit the emulator, do A:SYS QUIT
This emulator contains a large number of dev tools for CP/M:
Disks included are as follows: (also detailed when you run the app)
A: BOOT_UTILS (BOOT disk with CCP.COM and some utilies)
B: CPM3_SYSdsk (Disk with all CP/M 3.1 system utilities)
C: ./disksort/ (Connected to the (unix-)directory ./disksort/ (SOURCE))
D: DISKSORT.dsk (Submit examples of the DISKSORT project)
E: - User files - (appdata folder)
F: ZINC (System Utilies of the ZINC project from John Elliott)
G: TEST-UTILS-1.10 (Test Utilities of the old version yaze-1.10)
H: HI-C-Z280-Compiler (A Copy of the C Compiler from HI Tech Soft)
I: UNIXLIKE (UNIX like utilities)
J: MMU-Utils (Testfiles for the Memory Management Unit (MMU).)
K: Kermit_SZRZ (Kermit and SZ/RZ (Zmodem))
M: Turbo-Modula-2 (Modula-2 compiler of Borland)
N: testdsk (Scratch area - Disk image)
O: ZPM3N10 (ZPM3N10 the BDOS3 replacement from Simeon Cran)
P: BIOS3 (Sources of the BIOS3 for YAZE-AG)
See the HTML manual included which should be available in the usual menu.
Note that if you have no idea what CP/M is you should probably give this one a miss, it's a text only operating system that was very popular on Z80 and 8080 based computers such as the Altair, Amstrad CPC and PCW.