It as nothing to do with emo. It's true that the name screamo looks like scream and emo, but it's not emo with scream.
Screamo is a lot more musicaly violent than emocore.
Listen to Saetia or Circle take the square (both best screamo band), and tell me if it sound like Alexisonfire or the used. Those are emo core.. far smoother than screamo.

Really awful music that scene and emo kids listen to to be "edgy" or "unique", when in all honesty they are carbon copies of each other.

Screamo IS:
*A genre of music, specifically emotional post-hardcore, most of the time with an pop, techno or mathcore influence.

Screamo IS NOT:
*An kind of clique or group (unless that group being a band which labels themselves as screamo)
*A type of person
*A way to scream, that would be vocal fry, inhale, exhale, pig squeal, guttural growl, e.c.t
*An adjective of and kind, unless referring to a genre of music

a subdivision of the music genre of emo music which in turn is a subdivison of punk music, due to its growing popularity schools now have to distinct cliques within them, the preppy hollister mainstream brandname snobby fucks in which i and my comrades have no respect for, and the black everything striped shirt pierce lipped tards who insist screamo is metal when infact its just another 20 year old dipshit who can get over their insignificant feelings.

emo and screamo tend to be different because screamo has lead "singers" who tend to cry louder than their emo counterparts. both emo and screamo tend to have the same chords and lack of musical genius which is supported by the solo being the same base rythem with just distortion. although they tend to be opposite of the mainstream people the tend to have their own culture which is no longer underground, they thrive because pop and emo music is constantoly played and overplayed on the radio giving most people who reject the brandnames a style to go for, this in turn creates a large subculture of similar lanky looking pale faced people who try to be different but just blend in to every hallway and street. those that actually want to be different need to explore themselves before they explore music.

A subgenre of emo that was invented when emo turned mainstream. The word Screamo is usually used to describe metalcore and heavy post hardcore that have emotionally charged lyrics, which are often screamed. The emotions used in Screamo songs are usually more angry than whiney, but can still be very whiney. Anger IS an emotion, but MTV seem to think otherwise! Real emo/screamo comes from real emotions, not fake whiney bullshit emotions that the emo singers don't even have.

Emo's answer to Hardcore.

1. Screamo is REALLY a type of music that died out in the 90's. It is NOT screaming emo.
2. Today, most people DO think screamo is screaming emo. If somone says they listen to screamo now days, they most likely mean they listen to emo music with more yelling.