pastordon, think of Windows 2000 has NT 5.0 and Windows 8.1 as NT 6.3. Underlying it's pretty similar, uses NTFS, MMC is similar, supports Active Directory, it is just really old and hasn't had any security updates since 2010. I'd question a company's IT department using it in a production environment. The last time I saw Windows 2000 being used in production was three years ago by an IT manager that set it up new as a DHCP server at a new office because a) they were too cheap to use a newer OS and b) she didn't know how to setup a DHCP server on something open source like *nix.