Screamo is not emo. its much closer to brutal death metal. many metal bands use Screamo (pig squealing) in their music. emo music is bands like simple plan and is about as far from screamo as it gets. screamo is about pushing the music you make to its limits and giving 110%
Screamo Bands are band like Devil Wears Prada or Alesana. Emo music is Simple Plan or Secondhand Seronade.