Genuine Question: What is Emo Music?

As some who’s like- embarrassingly new to the Alternative subgenre of music, I have a really hard time telling what exactly classifies as ‘Emo’ music. And I swear to god I’m being genuine- I just really wanna know. Because apparently, a lot of the bands I listen to don’t actually qualify as Emo, but are lumped into the group by association. I ask cause like- I’m asked what kinda music I listen to, and I usually just say “Alternative” cause that’s just what I’m really into right now. I don’t want to accidentally call a band that isn’t Emo, Emo- you know?

Also, could someone explain the difference? Again, this is genuine, and my way of trying to educate cause I really love the music I listen to and wanna be able to properly identify it! 

- XOXO