Note
The most common form of nixie tube has ten cathodes in the shapes of the numerals 0 to 9 (and occasionally a decimal point or two), but there are also types that show various letters, signs and symbols. A related device is the pixie tube, which uses a stencil mask with numeral-shaped holes instead of shaped cathodes. Some Russian nixies, e.g. the IN-14, used an upside-down digit 2 as the digit 5, presumably to save manufacturing costs as there is no obvious technical or aesthetic reason.
The Nixie display was developed by a small vacuum tube manufacturer called Haydu Brothers Laboratories, and introduced in 1954 by Burroughs Corporation, who purchased Haydu and owned the name Nixie as a trademark. The name Nixie was derived by Burroughs from "NIX I", an abbreviation of "Numeric Indicator experimental No. 1". Similar devices that functioned in the same way were patented in the 1920s, and the first mass-produced display tubes were introduced in the late 1930s by National Union Co. and Telefunken. However, their construction was cruder, and they failed to find many applications until digital electronics reached a suitable level of development in the 1950s.
Burroughs even had another Haydu tube that could operate as a digital counter and directly drive a Nixie tube for display. This was called a "Trochotrons", in later form known as the "Beam-X Switch" counter tube; another name was "magnetron beam-switching tube", referring to their similarity to a cavity magnetron. Trochotrons were used in the UNIVAC 1101 computer, as well as in clocks and frequency counters.
