In 1936 – Edwin Armstrong presented FM radio at FCC headquarters. Armstrong played a jazz record over conventional AM radio, then switched to an FM broadcast. “[I]f the audience of 50 engineers had shut their eyes they would have believed the jazz band was in the same room.”
In 1946 – The first mobile telephone call was made from a car in St. Louis, Missouri.
In 1997 – Programmers deciphered code written in the impenetrable Data Encryption Standard, the strongest legally exportable encryption software in the United States. The hackers organized over the Internet and cracked the software in five months, proving that stronger encryption was needed.