The original version of this story appeared in Quanta Magazine. In our increasingly digital lives, security depends on cryptography. Send a private message or pay a bill online, and you’re relying on algorithms designed to keep your data secret. Naturally, some people want to uncover those secrets—so researchers work to …

The original version of this story appeared in Quanta Magazine. We all know to be careful about the details we share online, but the information we seek can also be revealing. Search for driving directions, and our location becomes far easier to guess. Check for a password in a trove …