PGP

PGP is an encryption program created by Phil Zimmermann in 1991 for signing and encrypting email and files. It popularized the web-of-trust model, where users vouch for each other's keys instead of relying on central authorities. The OpenPGP standard that grew out of it is still used for secure email and software release signing.

• Proton Mail → Encrypted email from Switzerland with PGP built in, no key wrangling required. End-to-end encryption only applies Proton-to-Proton or with PGP contacts; mail to ordinary inboxes travels like ordinary email.

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