If you want to make sure that no one intercepts your message, you want to consider faxing. Fax machines work off-line, keeping your communication off the World Wide Web, where no hacker can intercept your message.
This feature has made entities like Russia, America, and Iran turn to what would seem like obsolete technology from time to time. For Russia, the year was 2013, when typewriters made an unexpected comeback to preserve secrecy.
Fax machines can preserve the confidentiality of your message because they use landline phone networks. This method of communicating promptly and securely can be quite expensive depending on the distance.
Only the people receiving the printed message on paper will see it.
Encrypted fax messages offer even more security. The United States and Iran turned to encrypted faxes to communicate discretely as the threat of war loomed over the two nations.
Even though a fax demodulator can decrypt a fax message, an encrypted fax has an added layer of security that makes it virtually impenetrable.
Law enforcement agencies, Defense ministries, large corporations, and hospitals still use fax to relay medical records, legal documents, contracts, signatures, and other sensitive information.
The IRS is one of the major users of Fax for sending and receiving documents.