You can password-protect any type of file in Linux, which is useful if you want to store it in the cloud or carry it around in a USB stick.
With Linux, we will encrypt a file using gpg, which is part of GnuPG.
gpg -c filename.txt
Consider the following scenario: I have a file called my-personal-info.txt
gpg -c my-personal-info.txt
Upon running the command, the following output is displayed:
$ gpg -c my-personal-info.txt Enter passphrase: Repeat passphrase:
gpg has now created a file called my-personal-info.txt.gpg, which has been encrypted. The original file is still there, so you may want to erase it, transport only the encrypted file, or e-mail the encrypted file.
To decrypt a file just enter this command.
gpg -d my-personal-info.txt.gpg
A new copy of the file will be created after you enter your password or passphrase. The idea of storing passwords to important sites in this way is a good one.