Three types of fasting (Sawm) are recognized by the Qur’an: Ritual fasting, fasting as compensation for repentance (both from sura Al-Baqara), and ascetic fasting (from Al-Ahzab).

Ritual fasting is an obligatory act during the month of Ramadan.Muslims must abstain from food, drink, and sexual intercourse from dawn to dusk during this month, and are to be especially mindful of other sins. Fasting is necessary for every Muslim that has reached puberty.

The fast is meant to allow Muslims to seek nearness to God, to express their gratitude to and dependence on him, atone for their past sins, and to remind them of the needy. During Ramadan, Muslims are also expected to put more effort into following the teachings of Islam by refraining from violence, anger, envy, greed, lust, profane language, gossip and to try to get along with fellow Muslims better. In addition, all obscene and irreligious sights and sounds are to be avoided.

Fasting during Ramadan is obligatory, but is forbidden for several groups for whom it would be very dangerous and excessively problematic. These include pre-pubescent children, those with a medical condition such as diabetes, elderly people, and pregnant or breastfeeding women. Observing fasts is not permitted for menstruating women. Other individuals for whom it is considered acceptable not to fast are those who are ill or traveling. Missing fasts usually must be made up for soon afterward, although the exact requirements vary according to circumstance.