to know vs to know about

differences

Solution 1:

I know about electrical engineering -- I've read about it a few times and know more or less what it is.

I know electrical engineering -- I have a degree in the subject and know how to do engineering stuff.

I know about his pain -- I've seen him limp and I've heard him complain.

I know his pain -- I have similar pains myself and know what he's going through.

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