William Abel, a mail censor at Iowa's State Prison, Fort Madison, using a hot iron to bring out a secret message written in lemon juice on a letter.Three Lions/Getty Images Humans have had a long ...

For a long time, seeing those words pop up onscreen was the best indicator of good gossip to come. Close seconds included “OK, so…” for the more demure among us, or a simple teacup emoji for the ...

The arrests of ten people accused of working in the U.S. as Russian spies came after an investigation that dated back to the Clinton administration. Years of video and audio surveillance and secret ...

Do you ever feel like someone is peering over your shoulder while sending private messages to your friends and family? Well, you won't have to worry about those nosy people knowing what you're sending ...

Putting secrets in texts is risky business. An email is almost certainly a no-go, as is a traditional SMS. Encrypted texting, like iMessage, is better, since only your device and the recipient’s can ...

When we were kids, “invisible ink” meant lemon juice on notebook paper, write the message, and to see it someone would have to hold it up to the light for the words to appear. Otherwise, it just ...