Okay, so you know when you talk to people, sometimes you say "you" and sometimes you say "you all" or "you guys" when talking to more than one person? And sometimes people use "he" or "she" when talking about someone else?
Well, some languages have a special way of talking that's kind of like that, but even more specific! It's called the "t-v distinction."
Basically, in some languages, there are two different ways to say "you." One way is used for people you know really well, like your family or your best friend, and the other way is used for people you don't know as well or who are older or more important than you.
So, let's say you're speaking in French. If you were talking to your mom or your little sister, you would say "tu" which means "you." But if you were talking to a teacher or an older person, you would say "vous" which also means "you," but it's more polite and respectful.
It's kind of like how you might talk differently to your little brother than you would to your grandma or your teacher. In some languages, the t-v distinction helps people show respect and politeness in their conversations.