The operating systems I have collected include the following,
Early operating systems (patent protection)
TRS-DOS, ROM OS's
TI99 -4
Commodore PET, 64, and VIC-20,
First IBM-PC
Apple Computer
Sinclair Micro and QnX etc.
Non-Unix commercial operating system
CPM operating system
MP/M-80
UCSD P-system
p>Mini-FLEX
SSB-DOS
CP/M-86
DR-DOS
FreeDOS
p>
MS-DOS
PC-DOS
Mach is researched by Kananichi Mellon University
L4 microkernel second generation microkernel
CHORUS
Choices
Multics
OS-9
NSJ
Netware ：A network server operating system
Unix and similar systems
A/UX (Apple UNIX)
Unix
Microsoft Xenix
ChorusOS
Cromix
UNIflex
OS-9
IBM's AIX
BSD
FreeBSD
NetBSD
OpenBSD
DragonFly BSD
PC-BSD
Digital UNIX, later Compaq Tru64
DNIX
HP's HP-UX
GNU/Hurd
SGI's IRIX
Inferno
Linux (or GNU/Linux)
Mac OS X
MenuetOS
Minix
p>
OSF/1
Plan9
SCO's SCO UNIX
Sun's SunOS, later Solaris
System V
Ultrix
UniCOS
Kylin operating system (Kylin), developed by five companies: National University of Defense Technology, ChinaSoft, Lenovo, Inspur and National Star Corporation Server operating system developed in cooperation with the company
OS/390
z/OS
Syllable
Others
Acorn
Arthur
ARX
RISC OS
RISCiX
Amiga
AmigaOS
Atari ST
T
OS
MultiTOS
MiNT
Apple Computer (Apple/Macintosh)
Apple DOS
ProDOS
p>Mac OS
Mac OS X
Mac OS X 10.4 Tiger
Mac OS X 10.5 Leopard
Mac OS X 10.6 Snow Leopard (Alpha)
pink OS
BeOS
A/UX
Be
BeOS
BeIA
Digital/Compaq
AIS
OS-8
RSTS/E
RSX-11
RT-11
TOPS-10
TOPS-20
VMS (rear Renamed OpenVMS)
IBM
OS/2
AIX
OS/400
OS/390
VM/CMS
DOS/VSE
VSE/SP
VSE/ESA
OS/360
MFT
MVT
SVS
MVS
TPF
ALCS
p>
z/OS
PC-DOS
pink OS
Microsoft
MS-DOS
p>Xenix
Microsoft Bob
Windows based on MS-DOS operating system
Windows 1.0
Windows 2.0
p>Windows 3.1
Windows 95
Windows 98
Windows ME
Windows NT
Windows NT 3.5
Windows NT 4
Windows 2000
Windows XP
Windows XP SP1
Windows XP SP2
Windows XP SP3
Windows XP Media Center Edition
Windows XP Home Edition
Windows XP Tablet PC Edition
Windows XP Professional
Windows XP Professional x64 Edition
Windows Server 2003
Windows
Server 2003 64-bit Edition
Windows Vista
Windows Vista SP1
Windows Vista Home Basic
Windows Vista Home Premium
Windows Vista Business
Windows Vista Ultimate
Windows Vista Enterprise
Windows Vista Starter
Windows Server 2008
Windows Server "Longhorn" Web x86
Windows Server "Longhorn" Web x64
Windows Server "Longhorn" Standard x86
Windows Server "Longhorn" " Standard x64
Windows Server "Longhorn" Enterprise x86
Windows Server "Longhorn" Enterprise x64
Windows Server "Longhorn" Datacenter x86
Windows Server "Longhorn" Datacenter x64
Windows 7
Windows Server 2008
Novell
NetWare
Unixware
SUSE Linux
NeXT
NEXTSTEP (later Mac OS X)
Plan 9
Inferno
Prime Computer
Primos
Siemens
BS2000 - mainframe for Siemens.
SINIX (also known as Reliant UNIX) - UNIX computer system used by Siemens.