I am donating some old USB sticks to a charity. I need to make sure all my personal data is deleted before I ship them out. Is it enough to format the USB stick or is there something else I should do?

It is not enough to format the disks.

Many data recovery softwares can recover data / pictures from those drives after repeated formatting.

You need to wipe the drive (overwrite each sector with garbage data) to ensure the data can never be recovered.

Our Active@ KillDisk can do this. After running a multiple pass wipe no software will be able to recover data from it.