Archiving and encrypting in Ubuntu

1. Archive

Of course, you can use tranditional tar command
$ tar cvf archive.tar path

2. Encrypt

You can encrypt file using gpg
$ gpg -c archive.tar
This will prompt you for a passphrase and create an encrypted file acrhive.tar.gpg

3. Decrypt

You can decrypt the encrypted file using gpg.
$ gpg -d archive.tar.gpg