In my opinion, the first means that it is not A alone or B alone.
The second means that it is not A and B together.
Student or Learner
It seems to me that
- It's not A or B
- It's not A and B
both work. What do native speakers think? Are both correct and the same? Thanks
It depends what A and B are — in other words, the context.
YOU: 'What's your favourite meal?'
ME: 'It's not pizza or chop suey'.
'It's not bacon and eggs.'
'It's fish and chips.'
EDIT: MNY said the same thing a different way.