How does the NBA distinguish between offensive foul and blocking foul?

In another reasonable collision zone in the NBA, what is knocked down in the circle is considered a blocking foul. If it is outside the circle, it depends on whether the defender is moving. If it is moving, if there is physical contact, it is a block foul. If the defender does not move and the defender is hit, it is an offensive foul. That's my understanding. I hope I can help you.