Sawm (Arabic: صوم) is one of the most important aspects of Islam. It involves fasting. Fasting is done as prescribed by Islamic jurisprudence (Fiqh). In Islamic law, sawm means to not let anything pass your lips (food, water) as well as any sexual acts during daylight hours. When fasting ends depends on what branch of Islam they are part of. Sunni muslims fast until sunset whereas Shi'a fast until complete darkness.This kind of fasting during the holy month of Ramadan is one of the Five Pillars of Islam.