The first hacker in history was the magician Nevil Maskelyne, who in 1903 managed to intercept the first wireless telegraph transmission.
The first cracker in history was John Draper, also known as "Captain Crunch", who received that name because he discovered that by modifying a whistle that was given away in cereal boxes "Cap'n Crunch" emitted a tone at 2600 Hz with which it was possible to trick the telephone exchange and make free calls.