An Email Signing Certificate (S/MIME), short for Secure/Multipurpose Internet Mail Extensions, is a digital certificate that uses public-key cryptography to digitally sign and encrypt emails, proving the sender's identity (authentication) and ensuring message integrity (it hasn't been changed) and confidentiality (only intended recipient can read). It acts like a secure digital seal, preventing spoofing, tampering, and unauthorized access to sensitive communications, working across major email clients like Outlook, Gmail, and Apple Mail.
Corporate espionage and business email compromise (BEC) are rising threats. S/MIME certificates close the door on these risks by ensuring that your internal and external communications remain private and verified. It is the gold standard for secure email communication in enterprise environments.
