Saturday 19 October 2019

check digit

Whereas the title refers to a form of error detection, quality control through redundancy—the integrity of a numbering convention validated by a formulaic self-consistency, we were pleased to be elucidated in the origin of typeface E-13B, whose repertoire of characters, developed by Stanford Laboratories and General Electric in the late 1950s as a way to automate cheque-clearing, was the expression of a system developed for magnetic ink character recognition (MICR, a precursor to optical character recognition though in theory predating this earlier iteration that the technology was already acclimatized for).
E being the fifth font considered, B for the Beta-version, thirteen represented the size of the grid (see also, CMC-7 is the name for the parallel system utilised in parts of Europe and South America) for numerals and control characters: ⑆ transit, ⑈ on-us, ⑇ amount and ⑉ as a dash to break up long strings of numbers for human legibility. By measuring the resistance or conductivity at predetermined positions across the footer of the cheque, accuracy improved over other scanning techniques and human transcription. Little human intervention is needed, accounting for a fraction of a percent given the volume, though redundancies are still built in that requires a double-check and self-assessment.