What are the main rules and responsibilities of officials?

There are many roles of officials in Basketball such as:

Time keeper = the time keeper is in charge of making sure that the match doesn't over run

Referee = the referee is in charge of making sure that all rules are followed

Score keeper = the score keepers keep track of scores

Umpire = the umpire's fill in

Good Communicator = Good communicator or coach that supports the team