1840, "shape and size" (of a book), via French format (18c.), ultimately from Modern Latin liber formatus "a book formed" in a certain shape and size, from past participle of formare "to form," from forma "form, shape" (see form (n.)). Extended to computers by 1955.
format (v.)
"arrange into a format," 1964, in reference to electronic computing, from format (n.). Related: Formatted; formatting.
Please format this disk before entering data!
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