In Linux, you can format a floppy disk as a DOS disk or a Linux disk. The first floppy drive in Linux is /dev/fd0 and the second one is /dev/fd1. If you are using the second floppy drive, then just replace /dev/fd0 with /dev/fd1 in these instructions.
Formatting with a Linux filesystem
If you want a blank Linux formatted floppy, then you can use the command mke2fs. This will create an ext2 formatted disk.
Formatting with a DOS filesystem
First, you will need to install the dosfstools package:
aptitude install dosfstools
Then format the floppy:
To format a floppy disk for DOS, writing an empty MS-DOS filesystem to the disk in the process, use mformat, which is in the mtools package:
aptitude install mtools
Give the name of the "drive letter" as an argument of the disk to be formatted. Remember, when you format a disk, any existing information contained on the disk is lost.
To format the floppy disk in the primary floppy drive so that it can be used with MS-DOS, type like root user: