You may encrypt files for security.
To encrypt a file, open the terminal and use
cd directory bcrypt -c filename
After encryption, it will be renamed to filename.bfe.
To decrypt a file, use
cd directory bcrypt -c filename.bfe
If you have more than one file, it is ideal to compress them into a .tgz file first (there are other options).
To do this use
tar -cvzf name.tgz files-or-directories
This may now be made into an encrypted file, using the method above.
After decrypting it, extract it using
tar -xvf name.tgz