>If I go to upgrade my Win95 machine at home to NT workstation 4.0, am I going to have to format my hard drive?

If you're using FAT16 partitions, you do not have to reformat - NT can work with FAT16 partitions.

If you have FAT32 partitions, they must be reformatted if NT is to use them for the system (the partition where the boot loader) or boot (the partition where the NT operating system itself) is going to live.

FAT16 partitions can be converted to NTFS partitions using the NT CONVERT command once NT has been installed. Other operating systems (ie DOS, Win9x) can't access NTFS partitions natively, although there are limited third-party programs like NTFSDOS that will allow them to be read from DOS.

You may want to reformat in any case if you want to change how the drive is partitioned.

Realize that any WinAPps installed under Win9x will need to be reinstalled once NT is put in place; there is no tool to cenvert the Win9x registry to a WinNT registry.

Ed