ProtonMail Review: free encrypted mailbox in Switzerland (2021)
ProtonMail is an encrypted mailbox, which offer end-to-end encryption of your emails.
E2EE
End-to-end encryption is when the data is encrypted on the sender’s system or device, and only the intended recipient can decrypt it. As it travels to its destination, the message cannot be read or tampered with by an internet service provider (ISP), application service provider, hacker or any other entity or service.