I realize that since my work involves sometimes trying to find information that people try to hide this could be counter productive, frankly, there are good reasons to protect your data from other people. Things like financial records, private pictures, ideas for a business you plan to start, company trade secrets, lots of things that just should not be out in plain sight.
Storing things on your computer or phone or other device can leave it available to hackers or even just someone who randomly gets physical access to the device. Anti virus software, pass codes on the device, other things mean little if the info is stored as a simple file, like a word document or photo or video.
And sending a file by email or on a thumb drive or DVD is also risky. Unless the file is encrypted.
Enter some free software that can encrypt your file, called GPG – it comes as part of Linux operating systems and is available for Windows as GPG4win. It relates back to what was originally called PGP which was Pretty Good Privacy. It uses a two key system – a public key and a private key. There are phone aps that use PGP – these are not free but worth looking at.
You can use it to make an encrypted copy of a file that without your key (a long series of random characters – letters, numbers and symbols) the file is useless.
If you need someone to send you something – emailed or otherwise – they will need the free program on their end and your public key. The public key encrypts only – it will not change the encrypted file back, so it doesn’t matter who happens to get the file or the key, only your private key can unlock it.
Now that’s not to say that the NSA or someone with unlimited time on massive computers could not get the key, but as long as you are not a criminal or terrorist it is very doubtful anyone would be able to get your data.
As to storing the keys for your encrypted files, try one of these password managers in this article .