When you delete files on your computer, you are usually just deleting a link to the place on your hard drive where the data is stored. Before selling, donating, or throwing out any devices, it is advisable to wipe the drive to prevent anyone retrieving your private data, such as email, banking details, or browsing history.
Before completely removing important information from any device, it is a good idea to make a copy of the information in case there is something you need later on.
Using Windows to do a Factory Reset is known to leave files behind. There are better ways to achieve a good result using Windows, but those methods are more for advanced users.
Physically destroying the drive in any device is one simple method, the other is to use software to wipe the data from them.
Suggested free software:
DBAN (Darik’s Boot and Nuke) is hard drive disk wipe and data clearing utility, and is free for personal use, but not recommended for SSDs (solid state drives). This method requires creating a bootable disk, or usb stick.
Eraser Erases files and folders.
Kill Disk for Windows, Linux and Mac.
AOMEI backup software, or partition software can be used to wipe disks.
How to Wipe Disk Completely with AOMEI Backupper
How to Wipe Data on Hard Drive and SSD Permanently
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