Environment Variables
| Name | Description | Windows 2000 | Windows 95/98 |
| System | User | Process | Process |
| NUBER_OF_PROCESSORS | Number of processors running on the machine. | X | | X | |
| PROCESSOR_ARCHITECTURE | Processor type of the user's workstation. | X | | X | |
| PROCESSOR_IDENTIFIER | Processor ID of the user's workstation. | X | | X | |
| PROCESSOR_LEVEL | Processor level of the user's workstation. | X | | X | |
| PROCESSOR_VERSION | Processor version of the user's workstation. | X | | X | |
| OS | Operating system on the user's workstation. | X | | X | |
| COMSPEC | Executable file for the command prompt. | X | | X | X |
| HOMEDRIVE | Primary local drive (typically the C drive). | | | X | |
| HOMEPATH | Default directory for users (typicall Sersdefaultin Windows 2000). | | | X | |
| PATH | PATH environment variable. | X | X | X | X |
| PATHEXT | Extenstion for executable files (typically .exe, .bat, or .cmd) | X | | X | |
| PROMPT | Command prompt (typically ). | | | X | X |
| SYSTEMDRIVE | Local drive on which the system directory resides (typically C:). | | | X | |
| SYSTEMROOT | System directory (for example c:winnt). This is the same as WINDIR. | | | X | |
| WINDIR | System directory (for example c:winnt). This is the same as SYSTEMROOT. | X | | X | X |
| TEMP | Directory for storing temporary files (for example c: emp). | | X | X | X |
| TMP | Directory for storing temporary files (for example c: emp). | | X | X | X |