Ob-
/ob/
pref. Obligatory. A piece of netiquette
acknowledging that the author has been straying from the newsgroup's
charter topic. For example, if a posting in alt.sex is a response
to a part of someone else's posting that has nothing particularly
to do with sex, the author may append 'ObSex' (or 'Obsex') and toss
off a question or vignette about some unusual erotic act. It is
considered a sign of great winnitude when your Obs are more
interesting than other people's whole postings.
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