S/MIME is the most widely-supported method for secure email communication. With S/MIME, you can exchange signed and encrypted messages with others.
is proof that a message hasn’t been tampered with or sent by an impersonator.
In other words, it guarantees a message’s integrity and authenticity.
scrambles a message so that it can only be unscrambled by the intended recipient.
In other words, it guarantees privacy and data security.