What is the difference bettwen a coach and a referee?

A coach is a person who teaches and guides someone or a team to achieve their best performance as in singing, acting, or sports.

A referee is a person who stands between opposing competitors (individuals or teams) and has authority to decide whether the rules of the competition were followed, to assess penalties during a competition for breaking the rules, and to settle questions of whether or not a score or foul was made, etc.

Referees in various sports are known by a variety of titles, including: referee, umpire, judge, linesman, timekeeper or touch judge.

Coaches are partisan, always preferring the person or team they are coaching.

Referees are supposed to be objective, never favoring either side in the competition.