Not so much yelling. My mom is loud and abrasive by nature but everyone thinks she's the sweetest person ever by outside appearances. It's when she gets quiet or doesn't say much, that's when we were afraid.
whenever she said, "Let me think for a minute... or walked away", we knew that she was about to release the wrath of holy hellfire on our misbehaving asses.
my dad is complete opposite - very calm and quiet. If he ever lost his cool or changed his demeanor- we knew to stop.
my mom only yells at me know, if she sees me yelling at my kids. My son is quiet, stays to himself - the only time I really get on him is for acting up at school or crossing boundaries. My daughter starts tearing up or cries if she even feels like I'm getting ready to chastise her but I can't stay mad at either one of them for long. I usually end up hugging or cuddling them a few hours later when things calm down. Kids should never feel like their parents "don't like them" or like they're a burden.