Here is a simple and quick way for you to encrypt files in Linux:

gpg –output doc.gpg –encrypt –recipient EmailofRecipient@blah.com original_file.doc

Further explained:

• –output (or -o) is the name of the encrypted file
• –recipient (or -r) is the person who will be decrypting the file. If the file is for yourself only, use the email address of your GPG key.

To decrypt:

gpg --output output_file.doc --decrypt doc.gpg

I recently used this to encrypt a sensitive file before placing it on my Dropbox account. Nice safe way to place a private document in the cloud.

Reference, GnuPG manual.