The IDF stands for Israel Defense Forces, which is the national military of the State of Israel. Every Israeli citizen over the age of 18 who is Jewish, Druze, or Circassian is required to serve in the IDF, although there are some notable exceptions. Israeli Arabs, religious women, married individuals, and those deemed unfit medically or mentally are exempt from compulsory military service. However, many of those exempt from military service do volunteer to serve in the Israel Defense Forces. Once enlisted, men are expected to serve for a minimum of 32 months and women are expected to serve for a minimum of 24 months. IDF soldiers serve in a variety of units, ranging from elite combat units to combat support units. The IDF is headed by the Chief of the General Staff, who is subordinate to the Israeli Defense Minister.