Windows NT Workstation and Windows 2000 Professional are versions of Microsoft's server operating system without the sophisticated network operating system functions built in. These operating systems were targeted at business, scientific, and academic users to provide them with a large number of features and increased stability. Both use the graphical interface similar to the one introduced with Windows 95.
Windows NT Workstation and Windows 2000 Professional will run most software for Windows 9.x/ME without upgrading. Most major software publishers have provided upgrades for products that would not run. There is a group of small software programs called drivers that tell the computer how to communicate with other pieces of hardware (monitors, disk drives, scanners, digital cameras, etc.) The drivers from Windows 9.x/ME tend to be incompatible with Windows NT/2000. Before upgrading a computer from Windows 9.x/ME to Windows NT/2000, it is best to see of the manufacturers of all of your hardware and software products have provided upgrades or new drivers.