A kind of strike is a form of protest used by workers to express their grievances. The term can refer to a variety of strikes, including a TEN strike (TEN), which is a strike that lasts for TEN days; a WILDCAT strike (WILDCAT), which is an unauthorized strike; a HUNGER strike (HUNGER), which is a strike in which participants refuse to eat; and an OIL strike (OIL), which is a strike in which workers refuse to work with OIL or other petroleum products. Finally, a sitdown strike (SITDOWN) is a strike in which workers occupy the workplace and refuse to leave until their demands are met.