What happenede to windows4, 5, 6?

[NickFitz]

Are you sure, I thought Win95 ran MS-Dos 7? The fact you could skip the Windows startup process into Dos mode for instance, and how dos apps ran fine in 95 (apart from lack of available base 640K memory) but only in compatibility mode in XP.
Happy to admit it's a bit more complex than that though.

Microsoft's Brad Silverberg offers this take on it (PDF, 43K) in a 1994 email:

We’ve included those parts of MS-DOS need to provide 100% compatibility. MS-DOS is thus embedded inside Chicago [Win95's code name] for the purpose of running dos apps and dos drivers. We'll run even the most difficult ones, via the "escape hatch" of Single App Mode, which runs a real mode msdos session. But Chicago is not "built on dos".

[d000hg]

Seems to be a popular misconception that these somehow ran on DOS, which wasn't true. What they were was a bit of a mish mash of 32-bit support, pre-emptive multitasking and 16-bit core components from Windows 3.1. It had the old 16-bit limits for a lot of things, and the old Windows 3.1 lack of protection.

The reason was memory. Win95 ran on 4MB, whereas the properly 32-bit NT3.51 at the time needed 16MB, and in those days that was a couple of hundred quids worth of RAM. And by the time the hardware did catch up, lack of games hardware drivers for the NT strain meant MS had to keep plugging away at their sad old 16-bit OS far longer than was healthy. Win2K should have been the OS for everyone, but it took a couple more years and XP to get there.

Are you sure, I thought Win95 ran MS-Dos 7? The fact you could skip the Windows startup process into Dos mode for instance, and how dos apps ran fine in 95 (apart from lack of available base 640K memory) but only in compatibility mode in XP.
Happy to admit it's a bit more complex than that though.

[VectraMan]

Win95/98 were still based on the old DOS-related versions.

Seems to be a popular misconception that these somehow ran on DOS, which wasn't true. What they were was a bit of a mish mash of 32-bit support, pre-emptive multitasking and 16-bit core components from Windows 3.1. It had the old 16-bit limits for a lot of things, and the old Windows 3.1 lack of protection.

The reason was memory. Win95 ran on 4MB, whereas the properly 32-bit NT3.51 at the time needed 16MB, and in those days that was a couple of hundred quids worth of RAM. And by the time the hardware did catch up, lack of games hardware drivers for the NT strain meant MS had to keep plugging away at their sad old 16-bit OS far longer than was healthy. Win2K should have been the OS for everyone, but it took a couple more years and XP to get there.

[NickFitz]

The Windows Team has all the details

Turns out that Windows 7 is actually Windows 6.1, to maximise application compatibility

[d000hg]

Win95/98 were still based on the old DOS-related versions. Win2000 was built from the separate NT core - Win95 and NT4 were quite different, and WinXP then followed this route also IIRC. So yes, 2000 & XP are built on the NT kernal to the best of my knowledge.

[BrilloPad]

NT4 was 4. Windows 2000 was 5. XP was 5.1. Vista is 6, and presumably Windows 7 is 7.

I think Win95 is also 4.0, Win98 was 4.10 and Me was 4.90.

A bit odd that they didn't consider XP was worthy of a major version number change. If anything that was the most significant change as that's when they merged the product lines.

Complete list here.

Many thanks chaps. I find it interesting that Vista is listed as NT6.0. Maybe I am a bit sad.....

[scooby]

NT4 was 4. Windows 2000 was 5. XP was 5.1. Vista is 6, and presumably Windows 7 is 7.

I think Win95 is also 4.0, Win98 was 4.10 and Me was 4.90.

A bit odd that they didn't consider XP was worthy of a major version number change. If anything that was the most significant change as that's when they merged the product lines.

But wasnt 2000 aimed at business, and the XP change was to implement that setup for home use? i think thats why they didnt give it a whole number!

95, 98 & ME where all based on the same OS... it is a little odd tho...

[voodooflux]

Complete list here.

[VectraMan]

NT4 was 4. Windows 2000 was 5. XP was 5.1. Vista is 6, and presumably Windows 7 is 7.

I think Win95 is also 4.0, Win98 was 4.10 and Me was 4.90.

A bit odd that they didn't consider XP was worthy of a major version number change. If anything that was the most significant change as that's when they merged the product lines.

[BrilloPad]

I remember windows 2, 3 and 3.1 : but what happened to 4, 5, 6? Presumably they correspond to certain windows versions : but which?

I know of 95, 98, 2000, NT, XP, Vista.