Environment variables
| Variable | Sample Typical Value |
| $SystemDrive% | C: |
| %SystemRoot% | C:\WINNT C:\Windows |
| %SystemDirectory% | C:\WINNT\System32 C:\Windows\System32 |
| %WinDir% | C:\WINNT C:\Windows |
| ___ | C:\WINNT\Program Files |
| %ComSpec% | C:\WINNT\system32\cmd.exe |
| %Temp% | |
| %HOMEDRIVE% | C: The drive letter associated with the user's home directory |
| %HOMEPATH% | The path to the user's home directory (excluding drive):\Documents and Settings\Guest |
| %OS% | Windows_NT The operating system the user is running |
| %USERNAME% | The user's name |