PGP is an open-source application that enables users to send out encrypted emails. Individuals utilize their public secrets to verify themselves. This means that others can verify who sent the email by checking if the sender unlocked the email with their private key. Use PGP to keep your communications private. It works with Windows, Mac OS X, Linux, iOS, Android, BlackBerry, etc.

S/MIME, known as Internet Engineering Task Force (IETF), is a standard used to deliver public-key encryption and digital signatures. This is now used in the latest email software services and was developed by RSA Data Security. S/MIME is similar to PGP in its functionality, but users need to obtain keys directly from a specific Certificate Authority (CA).

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