Linguistic doubt.

[Enrique]

Is an expression like "He don't know nothing about this", I mean the "He/she don't" and the double negation common among English speaking people? I find it everywhere in the (motion) pictures.

[Chris]

It's common among people who are not very educated, but it is also used as a kind of slang sometimes.

[Peter]

The correct way of saying this is 'he doesn't know anything about this'.

[Enrique]

Thanks Peter and Chris.