BAUDOT

Baudot refers to a family of 5-bit character encodings used for telegraphy and teletypewriter systems, named after the French engineer Émile Baudot who developed the system in the late 19th century. The Baudot code was designed to transmit text efficiently over mechanical and electrical telecommunication links and became foundational for early data entry and transmission devices.

The code encodes characters using five bits, providing 32 possible patterns. To accommodate a practical set of letters, digits, and punctuation, the Baudot system uses shift codes to switch between two mappings: letters and figures. When a shift to figures is issued, the same five-bit patterns map to digits and punctuation; a subsequent shift back to letters returns to alphabetic mapping. This reliance on mode switching is a defining characteristic of Baudot-based systems.

A widely known version of the Baudot code is ITA2, the International Telegraph Alphabet No. 2, which was extensively used by teletype networks in the mid-20th century. ITA2 and its descendants influenced many later 5-bit encodings used in early computer terminals and printers. Over time, 7- and 8-bit encodings such as ASCII supplanted Baudot in mainstream computing, but Baudot remained in use for certain telecommunication applications and tape-based systems for several decades, and it remains an important topic in the history of data encoding and telecommunications.

In summary, Baudot denotes an early, influential 5-bit character encoding used for telegraphy, notable for its letter/figure shift mechanism and its role in the development of teletype and early computing interfaces.