Full-time employees generally work 38 hours a week. They are paid for a full week’s work and receive benefits like paid annual leave and sick leave.
Part-time employees work less hours than full-time employees but generally receive the same benefits. These are calculated on a proportionate or 'pro rata' basis. If you are employed part-time you will usually work regular hours or shifts.
Casual employees work on an hourly or daily basis and are less likely to have regular or guaranteed hours. They do not get paid sick leave or annual leave, but the pay rate is usually higher to make up for this.