She sees the bright side of other people's irritating IT fog (8)
I believe the answer is:
optimist
'she sees the bright' is the definition.
I can't tell whether this definition defines the answer.
'side of other people's irritating it fog' is the wordplay.
'side of' indicates taking the first letters (the letter from one side of the word).
'irritating' indicates an anagram (letters irritated or excited).
'fog' becomes 'mist' (mist is a kind of fog).
The initial letters of 'other peoples' is 'op'.
'it' anagrammed gives 'ti'.
'op'+'ti'+'mist'='OPTIMIST'
Can you help me to learn more?
(Other definitions for optimist that I've seen before include "One looking on bright side" , "One always sees the glass as half-full" , "One wearing rose-tinted spectacles" , "Cheerful sort" , "Glass-half-full person" .)