Erasing data for good is more difficult than you would think, because there are various ways to delete and erase! The necessity of erasing data securely is however demonstrated yet again by a current case which occurred in the canton of Zurich.
As reported by various media, IT devices were not correctly disposed of in the canton of Zurich. That’s how it was possible to retrieve confidential data from several hard drives, ending up with various people involved in the Zurich sex and drug scene.
This case demonstrates just how important it is to delete sensitive data – which is not so difficult at all: Data can be irrevocably obliterated by physically destroying data carriers. A more workable alternative though is “deletion by overwriting” using special software. These overwrite the areas on a data carrier containing data to be deleted with (random) data patterns – usually several times. This process will erase data irretrievably.
You can find out how you can securely erase data carriers such as hard drives, USB sticks or SD cards and smartphones or tablets and learn about the alternatives available (encryption) here.