Changing the format of a partition

["Adelle Hartley" <adelle@bullet.net.au>]

Hi all,

I've been running Debian 3.0 for a while now, and I want to change the
format of one of my partitions from FAT32 to a native Linux format.

Google has pointed me in the direction of "mkfs", but if I type

mkfs /dev/hdd

I get the message "mkfs: command not found".

Is this the right command?  And do I need to unmount the drive first?

Thanks.

Adelle.