To show the numbers calculated by the computer (as by the beginning computers were only used as calculating machines) lamps were used. A big advantage then were ten cypher-shaped masks to show the results directly...
The seven-segment-display - because its simplicity it is the standard at pocket calculators. Despite its ability of 128 (2⁷) combinations it is unable to show text. And it is restricted to only one size of signs.



To show all (capital) letters of the alphabet and all cyphers ("alphanumeric") the improvement to a 16-segment-display was attemted but could not succeed.


Many uses got the "Dotmatrix" with 7 (and more) lines and a row of 5 columns per letter. It is in use especially for running text (e.g. for information in public traffic).


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