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I have some time now so I can finish off my discussion of old Windows versions. I know this is somewhat OT now, but this thread started with a lot of old wives' tales about pre-95 versions of Windows being flung around (which happens all the time, as it turns out).

DOS + real-mode Windows (Windows 1.0)
This is the closest Windows ever was to just "running on top of DOS". As we all know, DOS is a real-mode OS. The first versions of Windows also ran in real-mode, and relied on DOS for many device drivers and for file system access. However, Windows was more than just a GUI, as it provided support for co-operative multitasking, which DOS lacks.

DOS + 16-bit protected-mode Windows (Windows 2.0 a.k.a. Windows/286, Windows 3.x in "Standard Mode")
This required at least a 286 to run. Windows apps now ran in 16-bit protected mode, but they all ran in the same address space. I think to run DOS apps Windows had to temporarily quit to get back into real-mode.

DOS + 16-bit protected-mode Windows + 32-bit protected-mode kernel (Windows 2.03 a.k.a. Windows/386, Windows 3.x in "386 Enhanced Mode")
Yes, before Windows 95 there was actually a 32-bit protected-mode kernel called the VMM (which is the kernel for 95, 98, and ME as well). It runs separate "virtual machines" in V8086 mode using pre-emptive multitasking, so you could actually run multiple DOS apps simultaneously. This was the introduction of 32-bit VXDs (virtual device drivers) that allows the VMM to share devices among the different DOS VMs. One of the VMs was designated as the "Windows VM". It ran in 16-bit protected mode and ran all the Windows apps in one address space, still using co-operative multitasking.

DOS + 16-bit & 32-bit protected-mode Windows + 32-bit protected-mode kernel (Windows 95, 98, ME)
Windows 95 added support for 32-bit Windows apps. This was the debut of Win32 in the consumer OS line. It still used the VMM to multitask DOS VMs using V8086 mode, and there was still one VM designated as the "Windows VM". However, the Windows VM now ran in 32-bit protected mode and was further sub-divided into separate address spaces, one per Win32 process, and added an extra level of scheduling so that Win32 processes could be pre-emptively multitasked. However, they left a large chunk of each address space mapped to the Win16 area so that old Windows apps could still run using co-operative multitasking in a shared memory space. Also, a lot of the USER and GDI code in the "new" GUI was still 16-bit code, which caused performance and stability problems. It was very hacky.

One notable thing about Windows 95 was that if you installed all 32-bit protected-mode drivers (VXDs), then Windows was no longer "running on top of DOS" in any real sense after starting up, although it still needed DOS to boot. From the user's point of view, DOS was no longer a separate product, but it was still there (DOS 7.0).

There's a lot of good background info here.

SandeepMathew wrote:I know perfectly well that windows conforms to POSIX i do know which
version ... but Windows 2000 server is posix compliant... and so r the
future versions..............

1003.1 which doesn´t say much.

@Colonel Kernel:
I had a feeling that there was a version of Windows 3.x that ran in some type of protected mode -- which I had somehow always assumed over the years to have been thirty-two bit, but it makes sense that you say sixteen bit -- of course I am not arguing about sixteen or thirty-two bit just noting that I found that bit enlightening for those memories from my childhood.

The reason I say this is because at that time I was around ten years old, and I remember some how booting or getting into some type of configuration screen where you could either change or view the mode Windows was running in..from DOS I think.. I can not say much else since it was so long ago.. Anyway. That was a really interesting post that I liked reading.

Kevin McGuire wrote:The reason I say this is because at that time I was around ten years old, and I remember some how booting or getting into some type of configuration screen where you could either change or view the mode Windows was running in..from DOS I think..

I remember that too, but also only vaguely. I read on TechNet that the VMM is a replacement for WIN386.EXE -- maybe that's how you used to start Windows 3.x in "386 Enhanced Mode"...

Who would have thought we could get nostalgic for crappy, hacky, 16/32-bit hybrid OSes.

Colonel Kernel wrote:Who would have thought we could get nostalgic for crappy, hacky, 16/32-bit hybrid OSes.

It's weird. I have a warm fuzzy place for Windows 95 for some reason....

Alboin wrote:

Colonel Kernel wrote:Who would have thought we could get nostalgic for crappy, hacky, 16/32-bit hybrid OSes.

It's weird. I have a warm fuzzy place for Windows 95 for some reason....

I was more of a Windows 98 person myself. I would most likely still have it if people still wrote drivers for it.

You people scare me considerably..

I had more fun using dos than windows .... Back in School we had pc's
with no hard drives .. The instructor would put a dos boot disk and
then a disk containing qbasic and logo.....

We use have fun playing good ol dos games ... we also had fun with
logo .. when instructor is not watching we would type something like...
kick (or ****!) .. and it would reply "i do not know how to kick" --- that was fun....!


Then later i learned how to program the vga and got interested in
dos game programming and os development was "spawned()" from
this.....

Oh for those days of trying to get games working under a DOS extender! The worst I remember was Privateer II: The Darkening, which was extremely fussy about combination of flight stick, mouse, sound card and Vesa graphics version.

It was much more rewarding using software when you had to write batch files all over the place to get it working

Adam

It's weird how when there's a Windows vs. Linux discussion, most people defend Linux. Yet when it's OS X vs Windows, most people defend Windows.

Maybe it's not defending Windows per se - it's more of a "defending the PC vs. the Apple Maggotbox"

Cheers,
Adam

MessiahAndrw wrote:It's weird how when there's a Windows vs. Linux discussion, most people defend Linux. Yet when it's OS X vs Windows, most people defend Windows.

I think most people in these kinds of discussions have used Windows a lot and have probably at least tried Linux for a while. I doubt many of them have spent any serious amount of time with OS X. I think ease-of-use is somehow threatening to their sense of self-worth...

Maybe it's not defending Windows per se - it's more of a "defending the PC vs. the Apple Maggotbox"

My Mac is a PC, it's just prettier and more trouble-free than most.

If you really want to continue this discussion, you'd best create a "Why does everyone (except Colonel Kernel it seems) hate Apple......?" thread.

I beg to differ about the trouble free thing, I have never had as much trouble with any other kind of computer as I have had with macs. I have locked up more macs then any other kind of computer and I mean really locked them up had to hold the power button down kind of locked up. Oh course that maybe because the IT people at my school have the intelligence of a monkey when it comes to fixing computers. It was an everyday kind of thing "Teachers the server has crashed, please shutdown your computers and wait for an announcement saying you may turn them back on."

Of course our school is poor so we end up with the cheapest macs you can get and they suck.

EDIT: I actually like the nicer macs. They have a place in this world for things like video and picture editing. I am just tired of the MAC vs. PC commercials that just plain lie sometimes.

...Are you running classic (pre-OSX)? I have NEVER had OS X lock up hard on me, but Mac OS 9 and earlier were quite susceptible to it...

niteice wrote:...Are you running classic (pre-OSX)? I have NEVER had OS X lock up hard on me, but Mac OS 9 and earlier were quite susceptible to it...

The ones that I am talking about that always give me so much trouble were OS X panther (IIRC). They were iMac G4s specifically. Oh they were so easy to lock up. Maybe they just weren't very well maintained. It was always funny because you could lock them up just by launching firefox. Sometimes force quit worked, but most of the time you would either have to wait for it too unlock up (which rarely worked) or just turn them off and then back on again.