IMHO
IMHO is an abbreviation for 'In My Humble Opinion' or sometimes 'In My Honest Opinion'. It often appears in emails, mailing lists and other electronic forums where abbreviations and acronyms are used to speed message composition.
It is often said (half jokingly) that when 'IMHO' appears, it is a sign that the writer has an overly high opinion of themselves, because nobody who truly was humble would use the word to describe themselves.
See also: Abbreviations used on the Internet, Internet jargon