And if she was able to do it, your grandma can do it too.
Now, most of us don't expect the FBI to show up or something, however if you decide to change hardware, replace hard drives, use this tool to completely wipe it off. Do this with any device you don't plan to use in the future.
Image: bleachbit.org
Hillary used bleachbit, a white noise cleaner available for Windows and Linux.
How she allegedly used it:
- Shredder E-Mails
- White Noise Free Disk Space
White noise means writing and overwriting free disk space until the traces of previous, probably restorable data, is non-restorable.
Think of it like writing something with a pencil, and erasing it. There are still little traces left, right? Now white noising would mean to write over this free space and erase it, rinse and repeat, until it is impossible to find out what you originally wrote.
TL;DR get this tool, and check its other features.
You never know when it comes in handy.
More on https://www.bleachbit.org/