Possible Duplicate:
How to format a USB flash drive?
How do I clear everything (data, viruses) from a thumbdrive?
How to format a pen drive in Ubuntu?
I have this pen drive which I made bootable using some other system (OS).
But I need to format it from my Ubuntu 12.04. Please guide me.
Open Disks program from dash:
Then choose your device from left. Make sure you have selected at least one volume, and click on format as below:
In case you can't get your device formatted from Method #1 try this way.
Open the Terminal (Ctrl + Alt + T)
List your block storage devices by issuing the command lsblk
Then identify your pen drive by it's SIZE. In my case its /dev/sdb
Erase everything in the pen drive (OPTIONAL):
sudo dd if=/dev/zero of=/dev/sdb bs=4k && sync
Replace /dev/sdb with your corresponding device. This will take some time. It will pretend to stuck. Just be patient.
Make a new partition table in the device:
sudo fdisk /dev/sdb
o to create a new empty DOS partition table. Make a new partition:
Press letter n to add a new partition. You will be prompted for the size of the partition. Making a primary partition when prompted, if you are not sure.
Then press letter w to write table to disk and exit.
Format your new partition.
lsblk/dev/sdb1 
Issue the command below to format the new volume:
sudo mkfs.vfat /dev/sdb1
Please replace /dev/sdb1 with your corresponding device.
Eject the device:
sudo eject /dev/sdb
You can try the application called Disks Utility. It's a very handy utility which should let you format the disk, among other things. You can find it by pressing ALT + F2 and typing the name, or going to System > Administration, or I guess typing the name in unity dash.
