Recently one of my friends told me that there is distinct difference between 'know of something' and 'know about something' expressions.
- 'know of' is used when you have personal experience with what you are talking about
- 'know about' is used when you have heard about the subject but never had any experience with it.
This contradicts with my experience. To me it seems like 'know about' is used in every situation and the use of 'know of' is mostly limited to 'not that I know of' expression. Short google search seems to support my point of view, there are articles named '10 things I know about journalism' where person is speaking from the experience and not that many encounters of 'know of' expression anywhere.
So, is my friend's statement true?