Yep, this is exactly it.
You obviously didn't say you weren't taught it in school, but t"period" is what most of the english-speaking world calls the little dots at the end of our sentences. And yes, hyphen is the correct term for - but a lot of us call it a dash. It's not incorrect, just another word for it.
Out of curiosity, what is the word you use for the dots at the end of sentences?
(And no, we're not disagreeing with you because you're a newbie - I've seen you post before and your name is familiar to me... and you've been here longer than I am, so you're certainly NOT a newbie by any stretch of the word - we're questioning you because you're making no sense.