Alphanumeric characters

The HP-41 series of HP printers from Hewlett-Packard were the first to offer an alphanumeric display in 1979, thus initiating the replacement of the up-to-the-minute seven-segment display displays with mostly red LEDs.

An alphanumeric character is in the strict sense either a letter or a number. In a wider sense, it is a number, a letter, or a special character (eg, point, comma, parentheses). The term finds use in telecommunications and computer technology.

The assignment of keyboard inscriptions is defined in the DIN 2137 valid for Germany and Austria.

The term alphanumeric character is mostly used to delimit numeric (only digits) and hexadecimal (hexadecimal digits only). Edit usagetext

Alphanumeric is often used to define a code or character set or to describe the properties and capabilities of an input or output device.

Historic phone numbers before self-service were often given as they were easier to remember.

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