Referees are people who are prepared to speak about your qualities and suitability and recommend you to an employer. Make sure you have their permission to supply their contact phone number!
If you have previously had a job, and you did well there, you should ask your former employer to be a referee.
Other responsible adults who can vouch for your capacity for work and favourable personal qualities are also suitable referees. Don't use a family member.
Remember to ask first!
Teachers in NSW public schools are not allowed to provide personal references on school letterhead, or mention their school.