QR codes–square, dot-matrix variants of the venerable UPC–are becoming an increasingly popular way to share information such as URLs, contact details, GPS coordinates, and calendar events. The idea is ...

Morse code encodes a simple text into a sequence of dots, dashes/dits, and spaces. It is one of the earliest methods used to transmit messages in the form of audible or visual signals. The Morse code ...

While efforts in Europe focused on Enigma, the outcome of the Pacific War hinged on intercepting and breaking Japanese naval ciphers—most notably the code known as JN-25. This code was a two-step ...