The directory where the core Microsoft Windows NT and Windows 2000 operating system files are stored. In a default installation of Windows NT and Windows 2000, the operating system files are located in C:\Winnt. You can specify different locations for these files when you set up Windows NT or Windows 2000.
The symbol %SystemRoot% is an environment variable that can be used in Windows commands at the command line or in batch scripts such as logon scripts. (Windows NT and Windows 2000 are case insensitive: %SYSTEMROOT%, %SystemRoot%, and %systemroot% are identical.) For example, if your current directory during a command-line session on a machine running Windows NT is
and you want to change to the directory where the Windows NT operating system files are located, you can type