If you are using linux but dont have enough knowledge to format a pen drive, give a look at following commands. You can format USB pen drive with the help of following commands:

[a] fdisk : Partition table manipulator for Linux

[b] mkfs.ext3 : Create an ext2/ext3 filesystem by formatting given
partition name (/dev/partition)

[c] e2label : Change the label on an ext2/ext3 filesystem

First make sure USB pen is not mounted. Click on Places > Computer >
Select USB pen >

Right click > Select Unmount Volume.

Let us assume that /dev/sda1 is your partition name for USB pen. To
format type the following
command (Open X terminal and type the command)

$ sudo mkfs.ext3 /dev/sda1

Caution: Careful while entering device/partition name; wrong name can
wipe out entire hard disk!!!

Now use e2label command to change the filesystem label on the ext3
filesystem located on device /dev/sda1:

$ sudo e2label /dev/sda1 usb-pen

You can also create an MS-DOS/Windows XP file system under Linux,
enter:

$ sudo mkfs.vfat /dev/sda1
Now you are ready to use USB pen.
there is a link of the web page from where i got this
** Ubuntu Linux format USB pen drive **
How do I format a USB pen drive under Ubuntu Linux for ext3 file
system?
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