Otaku is a world famous japanese subculture based on the obsessive interest in computers, mangas…
For those intereste in a more academic approach to the word :
Otaku is derived from an honorific Japanese term for another’s house or family (お宅, 御宅 otaku) that is also used as an honorific second-person pronoun (roughly equivalent to usted in Spanish). The modern slang form, which is distinguished from the older usage by being written only in hiragana (おたく) or katakana (オタク), or rarely in rōmaji, appeared in the 1980s. It appears to have been coined by the humorist and essayist Akio Nakamori in his 1983 series An Investigation of “Otaku” (『おたく』の研究 “Otaku” no Kenkyū?), printed in the lolicon magazine Manga Burikko, who observed that this form of address was unusually common among geeks and nerds. It was apparently a reference to someone who communicates with their equals using (unnecessarily) the distant and formal pronoun, and spends most of their time at home.
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