example family you can say: Hi!= Hello! =Salut, Bonjour.
It's better to say meet in the street a person you do not know. "Bonjour".
It's better to say meet in the street a person you know a friend where number friends. Salut!/Bonjour ! you can say : "hello!" too. / "salut!" , "bonjour"
just to think if tonight says: bonne nuit!, bonsoir! bonne fin de soirée!