Windows NT/2000 Homepage
They modified it to use the Windows API and renamed it to Windows NT 3.1 in 1993, which was a fully 32 bit operating system. There are rumors that runs that they also used code from an Alpha based operating system and that is why Windows NT still has Alpha versions. Windows NT 3.1 used the cheezy Windows 3.1 Program Manager interface. It probably did not become popular like OS/2 2.0 because of this and because it was not compatible with DOS, had no device drivers to work with and ran like a pig. Nonetheless, it could run Windows 3.x software pretty well. Mostly bug fix releases appeared until after Windows 95 release. Then, Windows NT 4.0 came out in 1996 with the new Win95 interface and a new driver model which made it run faster, but that broke some device drivers again. Windows 2000 was released February 17, 2000 using yet another device driver interface (WDM) which broke some more drivers working fine in NT 4.0.
Windows NT is a multi-user operating system. Although you cannot remote login like Unix (although Windows 2000 now comes with a Telnet deamon), local files can be protected with NTFS. Multiple desktops are also easily configurable. NTFS is also a journaling file system which means it does not have to check the disk on system crash. Although its reliably leads sometimes to be desired, so you need to run a chkdsk.
Eventhough NT is not a mature operating system yet (or ever? with all the add-ons they include at each release), it is sufficiently stable and reliable to be used as a workstation operating system. Windows NT interface responsiveness is very good and the GUI can very easily and nicely change resolution and color depth without any problem and without closing any applications. This makes it even more suitable as a workstation OS.
Windows 3.1 compatiblity is pretty well implemented, not that it matters much today.
Multithreading in Windows NT is well implemented which should make it a good multitasker.
In addition, Windows NT does not come with all the server software needed. It requires to buy more software (from Microsoft naturally, or other) which rises the price to build a complex server out of Windows NT. Licenses are also sold in small amount which is good for starting, but becomes much too expensive when needs increase.
Windows NT comes with no system wide or standard scripting language other than DOS batch files. However, Windows 2000 now comes with "Windows Scripting Host" which comes with Visual Basic Script and JScript (modified EMCA Script) modules. In comparision, OS/2 has REXX for a long time and all Unix like systems including BeOS all came from the start with a wide variety of languages like Perl, shell scripts and Tcl/Tk. This makes wide distribution of small programs best developed with easy interpreted scripting language a hard thing to do on Windows NT due to the fact that people will most likely have to install the scripting library in addition to the small scripts.
NTFS file fragmentation is another problem. What's worse is that Microsoft provides no defragmentation software with Windows NT. However, in Windows 2000, to circumvent the problem, Microsoft has included a very slow and inefficient NTFS5 defragmenter.
Windows NT recovery is very painful. NT cannot boot from a diskette to a command line (Windows 2000 can boot to a useless recovery console I had the displeasure of trying). No other operating system can write to an NTFS partition. A few costly utilities from various companies are available to either boot NT to a command line or write to NTFS partition from DOS, but Microsoft's solution is to plug the hard disk to another Windows NT machine to read and write the corrupted NTFS partitions.
Another problem with Windows NT is that all settings are stored in the (in)famous registry. All boot critical parameters are found in it. One has to use REGEDIT.EXE which means one has to boot to another Windows NT GUI to edit a corrupted registry.
DOS compatibility is virtually useless, not that it matters much today.
Microsoft fails to include real real-time features to Windows NT. Is it probably the reason why they are releasing yet another version of their aging OS, Windows which can do real-time processing by using kludges. Consequently, Windows NT multimedia subsystem is still in infancy. This has however changed for the best in Windows 2000.
Microsoft is well known for its questionable business ethics. It might not be the best company to deal with.