How to Completely Erase your Harddisk Pendrive

DBAN is a self-contained boot disk that automatically deletes the contents of any hard disk that it can detect. This method can help prevent identity theft before recycling a computer. It is also a solution commonly used to remove viruses and spyware from Microsoft Windows installations. DBAN prevents all known techniques of hard disk forensic analysis. It does not provide users with a proof of erasure, such as an audit-ready erasure report.

Download: http://dban.org/download

How to use DBAN:

Just download the iso file, burn it to a cd, and boot from the cd. You're good to go.

KillDisk is a Powerful and compact software that allows you to destroy all data on hard disks, USB drives and floppy disks completely, excluding any possibility of future recovery of deleted files and folders. It's a hard drive and partition eraser utility.

Download: http://www.killdisk.com/

How to use KillDisk: Download and install KillDisk and you're good to go.