Bro vs Mr-What’s the difference?

Differences Bro vs Mr—are  given below

Bro vs Mr
As a noun bro is brother; a male sibling. As an abbreviation Mr is an abbreviation of mister, a title used before the surname in theory, though not generally in practice, above some undefined social level, too old to be addressed as “Master”, not a knight or of some higher rank, and, in Britain though not in the United States, not entitled to be addressed as “Dr”.