As an acronym does not have much use in Spanish, the /U/ in many cases is for "University" ("University of Palermo", "Public University", . . . ) or more rarely by "Union" or "Unity" ("Popular Unity"). In English it appears more as an acronym for the companies Universal Pictures (cinematographic), United Press (journalism), Union Pacific (railway), . . . and also as a way to abbreviate user profile, urban population, or unit price. But the most curious (and erroneous) use is that of 'uP' as a "microprocessor", where someone saw a resemblance between the Latin /u/ and the micro symbol; ( micro ) , or even with the Greek letter mu; (mu) which is the one used as a replacement, and he put it in because it was comfortable on the keyboard.
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