* Formal: You use "vous" when addressing someone you don't know well, someone older than you, or someone in a position of authority. It's a sign of respect.
* Plural: You use "vous" to address multiple people, regardless of their age or status.
In contrast:
* Informal "you": The informal "you" in French is "tu". This is used when addressing friends, family, children, or people you know very well.
Examples:
* Formal: "Bonjour, vous êtes professeur?" (Hello, are you a teacher?)
* Plural: "Bonjour, vous allez bien?" (Hello, how are you doing?)
* Informal: "Salut, tu vas bien?" (Hey, how are you doing?)
Important Note: It is always polite to use "vous" when speaking to someone you don't know well. If you are unsure, using "vous" is always the safer option.