What is the X in X-mas?
c.1500, "person who prints books, etc.," agent noun from print (v.). As a mechanical device from 1859, originally in telegraphy. In the computer sense, from 1946. Printer's bible (c.1702) so called from mistaken substitution of printers for princes in Psalm cxix:161, which led to the misreading:
Printers have persecuted me without a cause.