There are various types of leave for workers, including family leave, sick leave, parental leave and vacation leave. Other less common types of leave are donor leave, to serve as a blood, organ or tissue donor; disaster leave, to serve as a volunteer for an organization that assists with emergencies or disasters; or jury duty leave. Paid leave is rarely required by law and is more commonly provided by employers as a benefit for their workers. Leave for workers is covered under a variety of state and federal laws. Leave provisions often vary for private and public employees and with limited exceptions, there are few leave requirements for private employers.