The word digital originally referred to human fingers.
The word digital entered English in the mid-fifteenth century from the Latin digitalis, meaning of or pertaining to a finger or toe.1 The Latin digitus meant finger, and because humans have long counted on their fingers, the word came to mean relating to numbers as well. By the 1650s, English used digital in both senses: fingers and numerical values.
The pivot to its modern meaning occurred in 1945, when mathematicians and engineers began using digital to describe computation performed with discrete numerical values, as opposed to the continuous measurements of analog systems.2
George Stibitz of Bell Labs had demonstrated a digital calculator as early as 1940.3 ENIAC, one of the earliest general-purpose electronic computers, was completed at the University of Pennsylvania in 1945.4 Within two decades, digital had migrated from engineering journals into common speech.
By the 1970s, the word had attached itself to watches, recordings, and cameras. By the 1990s, a "digital economy" was something governments convened commissions to study.
The transition from analog to digital reshaped the vocabulary of work. A digital native, a term coined by writer Marc Prensky in 2001, described someone who had grown up with networked technology.5 Digital literacy became a job requirement. Digital transformation became a corporate mandate.
The Latin word for finger became the defining adjective of an economic era. The original meaning, a body part used to count, persists only in the medical term for a finger examination.