email encryption

Email, one of the most pervasive and enduring technologies of computer networking, was invented in about a dozen places by dozens of people in the 1960s. It's hard to lay out a clear history of the technology because it's just so obvious—pretty much as soon as more than one person could use a computer, there was some kind of mail facility. These ranged from mainframe-centric systems where all of the users of a single computer could write messages to each other, to PC-centric systems where workstations would mount a network share to store and retrieve messages. Pretty much any scheme you can come up with for moving messages was probably in use somewhere from roughly the 1960s to the 1990s, by which time the ARPANET-derived family of email implementations had taken hold. This form of email has a clearer heritage, to Ray Tomlinson, who came up with the core idea that addresses could identify both a user and a host, and that some kind of open protocol could be used to send messages to…