The more notable of the other uses of the symbol are as a
star key on a
telephone keypad and on a
Viewdata keyboard. This usage first appeared in a 1973 US patent filing (3,920,926). Early prototypes of the touch-tone telephone used keys with a star and diamond shape. According to Bell engineer Doug Kerr, these were replaced with the sextile and octothorpe because those could be typed or approximated with the
ASCII character set or an office typewriter. ==See also==