Hello! Its not Hi and Hello.
You say привет to someone that is your friend or cousin because its cobsidered kinda rude.
You say здравствуйте to your teachers and other things. Привет meand hello, while здравствуйте kibda means: be healthy!
Hope it helped!
In what context can this be used. When someone says "hello this is George" I interpret it as George is the name of the speaker. When would someone say "hello this is my younger brother"?